= a variation on Carsharing, whereby the cars are member-owned; Relayride and Getaround, which have created marketplaces to allow consumers to rent their cars by the hour.
Important: "While fleet-based carsharing providers can offer a few cars at select locations .. peer-to-peer models allow for every vehicle in a community to be a shared vehicle". 
From the Wikipedia:
"Peer-to-peer car rental (also known as person-to-person car rental and peer-to-peer car sharing) is the process whereby an existing car owner makes their vehicle available for others to rent for short periods of time.
Peer-to-peer car rental is a form of person-to-person lending or collaborative consumption. The business model is closely aligned to traditional car clubs such as Streetcar or Zipcar, but replaces a typical fleet with a ‘virtual’ fleet made up of vehicles from participating owners. With peer-to-peer car rental, participating car owners are able to make money by renting out their vehicle when they are not using it. Participating renters can access nearby and affordable vehicles and pay only for the time they need to use them.
Businesses within this sector typically apply some form of screening of participants (both owners and renters) and a technical solution, usually in the form of a website, that brings these parties together, manages rental bookings and collects payment. Increasingly, an automated form of insurance and breakdown coverage will be applied to rentals that take place through the service in order to protect an owner’s existing insurance coverage.
As with person-to-person lending, enabling technology for this behavior has been the Internet and the adoption of geo-location-based service." (http://en.wikipedia.org/wiki/Peer-to-peer_car_rental)
"Carsharing revenues alone are projected to hit $3.3 billion by 2016, according to business research and consulting firm Frost & Sullivan." (http://knowledge.wharton.upenn.edu/arabic/article.cfm?articleid=2714)
"The companies use different formulas, but participating owners receive, generally speaking, about two-thirds of the rental proceeds. RelayRides says an owner of a midsize, late-model sedan who rents out a car for 10 hours a week could expect to clear about $3,000 a year.
The hourly fee to rent a car, including insurance, averages $6 to $8. Older cars can run as little as $3 an hour. Fancier models can run much higher — Getaround says it has Tesla Roadsters that go for $50 to $75 an hour.
All of these companies offer their own insurance coverage for their renters, which is supposed to put owners’ minds at ease. But only two states — California and Oregon — have passed laws to clarify that an owner will not suffer any repercussions should a car-sharing renter have an accident, says Robert C. Passmore, senior director of personal lines policy at the Property Casualty Insurers Association of America.
“In all the other states, legal ambiguity remains,” he says. “If a renter should be involved in a serious accident in those states, the victim can be expected to go after every party possible, including the car’s owner.” (http://www.nytimes.com/2012/02/19/technology/car-sharing-companies-link-owners-with-renters.html)
"To allay the worries of car owners, the driving records of renters are checked for recent serious violations.
Getaround makes it easy to start: participants use their Facebook log-ins, and owners can control who rents their cars.
“We have seen many owners get up right to the point of that first rental and hesitate, as if standing at the edge of a cliff,” says Sam Zaid, the company’s C.E.O. “We want people to be able to start gently, perhaps renting just to friends of friends and not requiring any technology.” The owner personally hands over the keys to the renter — a big inconvenience if the owner doesn’t care to meet every renter, every time — and renters pay for the gas.
RelayRides installs hardware in each car to control the door locks. A smartcard reader is mounted behind the windshield, and the renter presses the card against the glass to gain entry. The ignition keys are hanging by the ignition, so the car can be rented many times without troubling the owner. Gasoline is currently included in the rental fee, but the company says renters will pay for it in the future.
The RelayRides hardware also includes a GPS receiver and a cellular connection, so the company always knows the car’s location, as well as a remote off switch that prevents car theft.
The hardware costs RelayRides about $500, and the company installs it free. Mr. Clark looks forward to not having to install it in the future. RelayRides has announced a partnership with the OnStar division of General Motors, allowing renters to find, reserve and unlock G.M. cars with their cellphones via a factory-installed OnStar system.
JustShareIt, which started in January, requires most cars to have hardware like that of RelayRides, and offers a few other features for security monitoring of renters, like a sensor to detect sudden braking or signs of towing.
At JustShareIt, owners pay $249 for installation of the hardware required for most cars, as well as a $2.99 monthly fee for the bare-bones service that locks and unlocks the car. Both owners and renters can pay optional charges for extra reports and services.
Getaround says it has 536 active cars in San Francisco and San Diego and 80 beta users in Portland, Ore. RelayRides has 200 cars in San Francisco and Boston, and the newly opened JustShareIt has 60 cars and four motorcycles in the San Francisco Bay area." (http://www.nytimes.com/2012/02/19/technology/car-sharing-companies-link-owners-with-renters.html)
From Rachel Botsman :
By Jessica Scorpio:
"Peer-to-peer car-sharing solutions like Getaround offer an innovative and risk-free way to share your car and participate in the New Economy. As a car owner, you can make money by sharing your car when you aren’t using it. People in need of a car can get access to one nearby. The peer-to-peer model is the most scalable option and will spread the benefits of carsharing to more people than ever before.
This new model of car sharing also requires new technology. Similar to other solutions, Getaround has developed carsharing technologies such as the Getaround Carkit, which means the car owner doesn’t have to meet the renter with the keys. The soon to be released Getaround smartphone application will make it easy for owners to manage rentals and for individuals to rent a car in three easy steps.
Getaround provides insurance, support for the community, and facilitates payment. We aim to make sharing fun and easy while increasing people's awareness of car sharing. Core to our platform is community and finding ways to establish trust between near strangers. To reinforce this, renters and owners build a reputation through ratings on past rentals.
Many traditional car-sharing services (such as Zipcar) use a fleet model that’s intrinsically limited. While fleet-based carsharing providers can offer a few cars at select locations, Getaround's peer-to-peer model allows for every vehicle in a community to be a shared vehicle.
Peer-to-peer car-sharing programs, like Getaround, can help create a sense of trust and community around sharing. This will lead to higher percentages of people willing to share, while having a positive impact on the environment." (http://shareable.net/blog/share-your-car-join-the-new-economy)
Drive My Car Rentals – Launched in December 2008, DriveMyCar was the first operator to successfully commercialise the peer to peer car rental concept. Car owners pay a $25 AUS ($15 US) annual fee to list their vehicle. Drivers can search and book these vehicles online, with the site arranging the rental agreement, insurance and payments. In 2010 the service introduced a hybrid insurance product that automatically covers an owner's vehicle when rented, costing drivers $10 per day. In late 2010, the company expanded its service from short term car rental to include short term car leasing (1-12 mths) and also entered the insurance replacement vehicle market. The company intends to expand its service into Europe and the U.S. in 2011.
Autonetzer – Based in Stuttgart, the company started to test p2p-Carsharing in fall 2010. Since May 2011 the service is offered throughout Germany. An add-on insurance policy covers any kind of accident during the rental period regardless of the car owner's own insurance.
RentMyCar – Based in Konstanz as well as New York, their peer-to-peer car sharing marketplace was the world's first. The service launched in May 2001. The company offered free listings of personally owned car rentals on a marketplace type platform that allows car owners and potential renters to interact with each other and to negotiate their own rental rates and terms. The company provided a Virtual Vehicle Inspection Sticker (VVIS), a master keycard and personal car sharing search engine, and a business method using neighborhood managers. About 800 vehicles were offered for rental in its first two years.
rent-n-roll - Based in Hamburg, this company offers p2p-carsharing throughout Germany. It's possible for users to rent cars online and via an iPhone app. Rent-n-roll runs a scientific project in Geislingen with the University of Applied Sciences in Geislingen-Nürtingen to examine private carsharing in an area that is no centre of population.
In the Netherlands several parties are entering the market in 2011. All encountered barriers in the form of historical insurance models, particularly excluding peer to peer car rental. The most cited reason is that the perceived risks are hard to estimate. Competition in this small country, inhabiting roughly 17 million people, seems to become very strong as soon as multiple players are active. Nonetheless some parties seem to have cracked the insurance box and believe they can win over the market.
Livop.fr – Started in September 2010, this is the first P2P carsharing in France with no key exchange.
DEways – Offers free membership and secured, prepayed payments.
Buzzcar – Founded in April 2011 by Robin Chase, cofounder of Zipcar. Users find and reserve vehicles using the iPhone app or a computer. Buzzcar requires a key exchange, whether in person or at a pre-arranged drop spot.
Voiturelib - Started in June 2010, offers comprehensive insurance cover, secure payments, and social networking features. Voiturelib requires owner and renter to meet in person to exchange keys and sign the downloaded contract.
WhipCar – The world's largest peer-to-peer car club. They offer a bespoke, fully integrated insurance product, 24/7 customer support, break down cover on all bookings made and automated screening of all drivers and car owners who join the service. Whipcar differ from a conventional car club in that there are no membership fees and owners and drivers meet and hand over the keys directly. WhipCar raised venture capital funding from Delta Partners in October 2009. The service has over 40 makes of car available to rent at any time and is present in over 450 towns and cities across the UK. Within six months of launch, WhipCar had over 1,000 cars available to rent.  USA
RelayRides – RelayRides launched an initial pilot in Boston in June 2010. Their headquarters were relocated from Boston to San Francisco in early 2011, although they continue to operate in the Cambridge area. They are the first company to attempt to integrate the existing black box technology from car clubs into private car owner vehicles, with a business model closely aligned to that of car clubs. RelayRides offers a single insurance policy to cover their drivers during rentals and claim to allow car owners to earn up to $8,000 a year by renting out their cars.
Getaround – Based in San Francisco. Getaround uses web interface, smart phone and social graph technology to facilitate person-to-person car rental. They offer a product called "The Getaround Carkit", which enables keyless entry to a converted vehicle through the ability of a driver or renter to unlock a vehicle through their smartphone. Getaround launched in May 2011, and won the TechCrunch "Disrupt NYC" award. Currently they list cars in the San Francisco Bay area, San Diego and Portland,OR.
Sprideshare – Based in San Francisco. Sprideshare is set to a launch a pilot scheme in collaboration with City Car Share in late 2011. Their model is akin to RelayRides, requiring vehicles to be fitted with technology which enables them to be remotely unlocked. They have faced a major insurance barrier, rooted in California insurance law, but worked with California State Assembly member Dave Jones to create Assembly Bill 1871, which has changed insurance law to permit remuneration for personal vehicle sharing.
Go-op – Pittsburgh based start-up which is developing an online system for vehicle sharing that is environmentally friendly and provides revenue to car owners.
Jolly Wheels – Originated in New York City in December 2005 and introduced the peer-to-peer rental concept in 2009, with over 80 locations across the United States.
FlexiDrive - Launched in July 2011.
Social Car - Launched in July 2011, the first peer to peer car rental service in Spain.
- May 2001 – RentMyCar launches the first peer to peer car sharing marketplace.
- Oct 2008 – Drive My Car Rentals – launches peer to peer car rental service in Australia
- April 2010 – Whipcar launches peer-to-peer car rental service in London, UK.
- May 2010 – Drive My Car Rentals – website and service redesign – introduction of hybrid insurance policy product that works in conjunction with the owners existing car insurance.
- June 2010 – RelayRides launches Beta product in Boston
- November 2010 – tamyca launches all over Germany
- December 2010 – Getaround launches Beta product in San Francisco
- Early 2011 – Sprideshare set to launch in San Francisco
- Early 2011 – JustShareIt set to launch in California
- June 2011 - rent'n'roll launches all over Germany
- July 2011 - Social Car launches peer to peer car rental all over Spain