I've got linux on my 2nd gen ipod mini....it was very easy to install. just becarefull man...everything is unsupported so if something bad happens...its your fault.
www.ipodlinux.org
after you install podzilla i'd recommend getting floydzilla....its better looking and it has a gameboy emulator on it...but i wont go into that...just READ READ READ before you do anything to your iPod..
Good luck..
Kevin.