I’ve joined a bunch of friends in a quest to reverse engineer and write custom software for Sunplus SPMP305x chips. These chips are inside all sorts of chinese media players, particularly the fairly powerful kind with a camera, video playback, etc. The chip is based around an ARM926EJ-S core, but the peripherals around it are completely custom – check out the marketing blurb. Most current work is on reverse engineering the hardware interface so we can completely replace the default firmware.
If you’re interested and you have one of these or don’t mind spending $33 to get an interesting ARM machine, check out the wiki, Google Code project for the Prex port and other stuff, and my Git repository with a port of MINI and a bunch of client utilities for reverse engineering and testing the hardware stuff. Most importantly, however, come visit us at #spmpdev on the EFNet network! Most of the work and chitchat happens in the IRC channel.