This is a non-insurance 'insurance' technique for sharing healthcare costs, applied by Samaritan Ministries, a Christian group in the US
How will I pay my bills when I have a need?
You explain to your care providers (doctors, hospitals, etc.) that you do not have insurance and that you are a self-pay patient. The providers send their bills directly to you. You organize the bills, complete a Need Processing Form, and submit them to Samaritan Ministries. We will publish your need in the newsletter, and the members assigned to your need will be asked to send their monthly shares directly to you through the mail. You can use the money you receive in paying your bills."
Their FAQ is at http://www.samaritanministries.org/info/html/faq.html