Doom has long been the benchmark for playing retro games on a whole variety of electronic devices. If it can play Doom, it can play pretty much any game of a similar generation (as long as the source code's available). Enter iDoom, a Doom port for the iPod. This port isn't new, but the latest update features iPod nano support which performs much better than previous versions.
The game requires some element of risk (it requires hacking your nano to install iPod Linux), but once the game is up and running it's practically flawless. The sound and some controls are missing (sorry guys, you're stuck with the pistol) but overall iDoom looks very polished. Check out this very smooth video of the game in action. If two Swedish University students could create this port in between lectures and beer breaks, then why can't Apple give us anything more than a Breakout port to entertain us while we listen to our 8-bit classics collection?