So this is exactly the Richard Stallman model of software. Pay people to develop it, don't charge anything for the software and give away the source.

There is no economic incentive for the donors (they might get a mail program, might not, but they will never get their money back or a return on that money.)

I suppose rms originally imagined that someone like the mailpile people would take the money they were given to create mailpile and give it to some other developer to create the tools they need. However, as we see in this campaign, all the money they get will go toward feeding, housing, and insuring themselves. (wait till they learn about payroll taxes, that will make them fiscal conservatives in a hurry :-)

Like the parent comment I can see how this works in the "old" world (make a company, product, sell it, rinse and repeat) but am curious to see if it can work in this other way.