Free and open-source software is good for you and for the world.
It is, I tell you!
However, while a fair few will simply utilise keygens and illecitly obtained license keys for that “must have” functionality, there are ussually as good (or better) OpenSource/GPL licensed options. This site (http://www.opensourcewindows.org/) has a very cool collection of some of the best Windows software in this category – No adware, no spyware, just good software.
Do yourself a favor and check it out.