Free Software Foundation
The Free Software Foundation (FSF) is a non-profit organization based in Boston, MA, USA. FSF relies on support from individuals to carry out their worldwide mission to preserve, protect and promote the freedom to use, study, copy, modify, and redistribute computer software, and to defend the rights of all free software users.
The gpl-violations.org project tries to raise public awareness about past and present infringing use(r)s of GPL licensed software.
The ultimate goal is to make vendors of GPL licensed software understand that GPL is not public domain, and that there are license conditions that are to be fulfilled.
Open Source Windows
Links to some great libre software specifically for Windows users.