You can now get Wolfenstein on the iPhone. Not the Wolfenstein RPG, not a cheap Wolfenstein knock-off, the real deal, programmed and ported over by id's own John Carmack. And best of all, it's free.
Yes, seeing as he worked on it as a pet project, Carmack has decided to release the game as a free, open source project. While a few tweaks have been made to the game, mainly in the way things like your health and ammo are displayed, it's largely the same Wolfenstein 3D that id released in 1992.