My OS's.

1: Windows 95
2: Windows 98
3: Windows 98 SE
4: Windows 2000
5: Windows ME
6: Windows XP Home
7: Windows XP Pro
8: PHLAK 0.1
9: Debian Linux
10: FreeBSD
11: IcePack Linux
12: Gentoo
13: BeOS
14: Mandrake Linux
15: KNOPIXX
16: TurboLinux
17: Slackware
18: Suse
19: Windows 2003 Server Enterprise
20: Yellow Dog
21: RedHat 8
22: Redhat 9

Those are all i currently have. Most of the Linux OSs i didn't use because of my dial-up. All of them were downloaded from linuxiso.org. I don't have the exact versions of the linux OS's right now because I'm not at home and don't have my CD case with me.