Linux
Fedora 5-8
Read Hat 9
Centos 4.4, 5.0
Ubuntu, Xubuntu, Kubuntu
Gentoo
Knoppix
SUSE 9.1, 10, 10.3, SLED10 {Server|Client}
Zenwalk
Unix
Sun Solaris 10.0
PC BSD
OSX
Other,
Plan 9
http://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs
menuetos
http://www.menuetos.net/
Wow after typing it out I should just pick one and live with it.