Noctemware has ported Quake III to the Dell Axim X50v and X51v. The game requires the the Intel 2700g multimedia accelerator and is reportedly capable of about 15-20FPS. You will also need about 120-150MB of storage space and 64MB of available working memory.
Quake III is available for free (so is the source code!) but you will need an installed copy of Quake 3 Arena (with all patches) on your desktop. Refer to the ‘More information’ link for installation instructions!