An unofficial version of Quake for the DS handheld has been in the works since October 2006, apparently, with the homebrew wizards behind the new project now releasing a pre-release version of the game for DS owners to try out. The game can be had from here, though I am honour bound to point out that any downloading, installing etc etc is absolutely nothing to do with us.
The latest blurb on the game suggests that it is nearing completion, though dynamic lighting remains absent at present, while a number of graphical glitches persist. The network mode has also be omitted presently, though the developers insist that this will return and are in fact enthusiastic about the prospect of wireless multiplayer Quake on the DS.
The site and download assumes DS users are experienced with homebrew installations and the like, so those of you interested in giving this a whirl should probably do some reading first. The game is based on the shareware version of the title, and urges you to buy a full copy should you wish to play the full game.
Control-wise the developers have made interesting use of the DS' controls. The d-pad emulates the traditional 'WSAD' keys, while the touch-screen changes perspective.