If you run iPodLinux like I do, here’s a treat- DOOM for the iPod. Mostly playable I need to sift through the Doom post for some key binds. Can load game saves. Can save game. Plays all wad files: Doom I Shareware (won’t play demos), Doom II Shareware, Ultimate Doom, Final Doom wads, and Doom II. Also unless you want Doom to crash in the menu put the help files in the folder too. Link.
Play DOOM on your iPod