The Nokia N900 mobile computer may just have a 3.5-inch display and a 600MHz ARM Cortex-A8 processor, but it does have a PowerVR SGX graphics processor that is capable of providing OpenGL ES 2.0 support, albeit through a binary-only driver. While this hardware is not much, it is enough for some gaming even with the ioquake3 engine. The ioquake3 engine, which is the free software project founded around the open-sourced id Tech 3 engine, is used by games like World of Padman, Tremulous, Urban Terror, and other free software games. Now thanks to the world of Oliver McFadden, an ioquake3 port is running -- and running quite well -- on Nokia's N900.
Oliver previously wrote the Revenge utility (which eventually went 1.0) for reverse engineering ATI Radeon graphics cards and their binary Linux driver, but this was all prior to AMD becoming one of the most open-source friendly companies around. McFadden also hoped to create an open-source ATI video BIOS, but that didn't end up amounting to much. He has been involved with some other X.Org projects as well. However, he has since moved to Finland and was hired by Nokia.
While not working in his official Nokia capacity for this port, in his free time he has made the ioquake3 engine run on the N900 device. He confirmed this work on his blog and there is also a YouTube video (embedded below) from the Nokia Maemo Summit where he shows Quake III: Arena running on this tiny device. The ioquake3 packages for Maemo on the N900 can be downloaded now at Maemo.org.