two principle ways in which people make money with free software
development
	modern economic models around fs development closely resemble early models
	keep in mind that software freedom is as old as software
	"proprietarization" of software began in the 1970s
		apparently pioneered by IBM
		furthered by companies like "Micro-Soft"
			and Bill Gates who in 1976 published his Open Letter to Hobbyists
	software was usually, if not always, distributed with source code
		usually either at no cost or at the cost of making and shipping copies
	programmers were paid for the time they spent working on software
		not for the software itself
	we see the same thing today
		programmers are paid to work on software
		the software is distributed freely (w/o restrictions) often even gratis
	example: Linux
		powerful and stable high-performance kernel
		found in everything from TVs and phones to supercomputers
		as of 2010, >70% of work done on Linux is done by paid programmers
		at least 659 companies have supported development of Linux
			compare that to development of MS Windows, supported by one company
		AMD's recent hirings
			show that if you can improve a company's sw, they might hire you
	example: Qt
		flexible cross-platform application framework
		popular in desktop & embedded applications
		most developers are employed by Nokia
	example: GNAT
		Ada compiler, now part of GNU Compiler Collection
		developed by New York University under $3M contract from USAF in 1992
		(C) assigned to FSF and sw released under GPL
	why do companies pay for the development of sw that few people pay for?
		they have a financial interest in high-quality software
		many companies offer paid support for the software -- more later
		many sell hardware on which the software is run
			servers, wireless network adapters, cameras, TVs, phones, cars
		many see fs as a way to save money and avoid reinventing the wheel
			e.g. AMD and Coreboot (or so I suspect)
				AMD no longer has to pay for the custom development of BIOSes
				they use an existing fs solution, adapt it to work with their hw
	also, most software is custom software, which is technically free
		companies/people pay programmers to write software
		this software isn't released publicly
		but if there's 1 user, and that user has the rights, the sw is free
		free in a trivial sense
support
	with proprietary sw, only the copyright holder is allowed to understand sw
		only they can support it
		the support is a monopoly
	with fs, everyone is allowed to understand it and support it
	support is a free market
	individuals make money making changes to fs programs
		either supporting their own programs of any other fs programs
		again, paid to work, not paid for the work
	individuals & companies sell consulting services & support contracts for fs
		Cygnus, Red Hat (announced income last year of almost $1B), Canonical
		Nokia/Digia and Qt Partners
		AdaCore
		as Mark pointed out, also Sencha
		Debian has a list of 824 consultants in 63 countries
		FSF lists 86 individuals and companies offering services in fs
additionally, some people sell free software
	they can charge a fee for distribution, even of someone else's work
	it may go against the traditional fs development economic model
	but it's not inherently unethical or even illegal
	in the 1980s, RMS himself sold copies of GNU Emacs
		made about $1300/mo