There's much more going on here than a leftist software development model. It's about innovation, who can do it, when can they do it, and can they share their ideas. Stallman got his start on a university campus (MIT) where OS system software innovation and development was done by geeks and nerds just for the joy of learning and contributing to a common goal of improving a networked environment for *other* research.
A lot of Stallman's ideology is irrelevant. That doesn't make the open source software development model socialist. A community of geeks and nerds researching and developing software is anything but a commune; it's invariably one of the most rigidly regulated meritocracies you'll ever find. Moreover, they often find shrink-wrapped software (a la Microsoft) to be boring and inflexible. They want to do it their own way, and in many cases, they can and do.
The real popularity of open source development emerged later in the context of AT&T's UNIX system software, which was enhanced and extended to support the Internet protocols using millions of dollars in DARPA funding at Berkeley. To keep up with the Internet and to provide a useful environment to a team of researchers, you had to have UNIX. Some people were uncomfortable with the fact that they couldn't share their own personal innovations at one of these "source shops" (a laboratory with a UNIX source code license), so they started casting about for alternatives. XINU, MINIX, and after the big USL court case over the inclusion of a few lines of UNIX code in the Berkeley's NET releases, the unencumbered (unpolluted with AT&T code) 386BSD software emerged.
About this time, Linus Torvalds used what he had learned by hacking on MINIX to implement a clone of UNIX that would be more scalable, and would fully utilize the virtual memory subsystem of the Intel 386 architecture. Someone else added the NET3 Berkeley TCP/IP code (as I recall). The rest is history.
Meanwhile, you can be either a socialist or a capitalist with open source software. The licensing doesn't preclude anyone from modifying it and selling it again, so long as the source is always available. It's actually kind of cool, but it takes some analysis to figure out whether or not your latest idea is going to be legal with respect to basing a product on GPL'ed software. The bottom line: do what you like. It's the free marketplace of ideas.
Stallman is not widely respected outside of a narrow group of people who adore his eccentricities. Eric Raymond, an advocate of the OSS model, is an anarhcist and second amendment rights enthusiast. Does it bother you that some nuts have been attracted to the cause of the OSS model? Maybe it should, maybe it shouldn't. In any case, I think it takes both shrink-wrap and open source together to provide users and developers with the freedom they want to compute in the best possible way. It's really and truly a free market like none other.
For those interested in what the scientists at Bell Labs did after UNIX, see
http://www.cs.bell-labs.com/plan9dist/The Linux heads here should be REALLY happy with my next article. It will be about MICRO$SOFT and their history of IP theft "pump 'n' dump" and Anti Americanism. And as you've seen by this one being posted I DO keep my promises in this area.
I think the cold and slithery one's big error is to try to frame all human exchange which has an extrinsic value in terms of money.
The open source movement is, IMHO, a post capitalist phenomena, and could NEVER originate from a socialist economy, because open-ness and sharing which arises from individuals with open source, more or less SPONTANEOUSLY, is exactly opposite the state imposed sharing so characteristic of planned economies.
In a sense, state imposed sharing strangles spontaneous/open sharing by individuals in its crib, while capitalism creates the surplus and good will which allows skillfull and highly competent individuals to develop quality stuff and GIVE IT AWAY just for the heck of it, for personal satisfaction, respect amongst peers, or perhaps to set up a marketable name for themselves which will eventually lead to a higher paying job...
George Gilder in Wealth and Poverty is much closer to the mark where he shows that giving away the goods and providing a service to people is actually the pure essence of capitalism.