Donor Pooling Model
“Yet another model is the donor model: somebody who is known for creating great work can collect up donations in advance; when he has collected enough to fund the work, he builds it, and releases the game copyright-free when it's finished. The donors will have paid and everyone else gets it for nothing, but they get it first and perhaps some special recognition for their contribution. I'd be happy to put down $40 two years in advance for a new Sid Meier game, particularly if I knew it would be released copyright-free when it came out. And I bet a lot of other fans of Sid's work would say the same.
The donors have to trust that the developer will finish it, of course; but this is effectively how freeware development works now. Somebody makes a name for themselves with a piece of freeware; they ask for donations; the donations help to fund further work on a new version. So far it has only been tried on a small scale, but—as the mobile and casual games are showing us—there's still plenty of demand for small scale games in the world. (http://www.gamasutra.com/features/20051128/adams_01.shtml
A variant of this system, pioneered by cyberspace engineer Crosbie Fitch, are the Treshold Pledge Systems, which is already in place for music, except that people give pledges rather than donations. When the musician releases the work, she collects all the pledges made towards it. See http://www.quidmusic.com for details. (http://www.gamasutra.com/features/20051128/adams_01.shtml
See our overview page on Money Pooling systems.