Links to the sites I support:

Explosm.net - Fun
Rukola.com - Fun
Gutenberg.org - Free ebook project
Opera.com - Good web browser
Firefox.com - Good web browser
Paint.net - Opensource photoshop competition
Gimp.org - Opensource photoshop competition
Debian.com - One of the best and oldest linux distributions, my favourite
Ubuntu.com - One of the best linux distributions
Ultimate-guitar.com - Very good site for tabs for a guitar
Zeitgeistmovie.com - One of the best documentaries I've seen, strongly recommended!
OpenOffice.org - Very good opensource suite
Songbirdnest.com - Opensource itunes alternative project
Rockbox.org - Opensource mp3 player firmware