Without even realising, you and the companies you work for are benefitting directly from free software. Free software is often misunderstood, as it is more than just receiving software without monetary cost.
Free software, by definition is software that grants you rights to modify and redistribute the software as long as you publish your modifications in kind. This method of distribution is behind the majority of infrastructure that powers the entire internet, and can be found in anything from Set Top boxes used to record television programs, to your wireless router at home sharing your internet bandwidth.
The Free Software Foundation works on protecting these freedoms granted to software developers. Often there are legal issues that entangle free software developers, ranging from Intellectual Property claims (often predatory and false!) and also targetting legal proceedings at people who try to modify free software without releasing their changes. They also sponsor some key projects, and provide online information on free software practices and also advise on predatory software practises like consumer-hostile digital rights management and anti-competitive measures taken by some proprietary software vendors.
Learn more about free software here, read the Free Software Definition:
http://www.gnu.org/philosophy/free-sw.html
Join the Free Software Foundation:
https://www.fsf.org/associate/support_freedom/join_fsf?referrer=6008