Ran across this case while shopping for camera accessories at Circuit City. It is a semi-hard case (feels like it is made of car tire rubber coated in faux-leather). Best fit I have found for the GP2X. It is just a TINY bit shallower than I would like, the joystick stays 'clicked' when it is closed, but I don't think that will be a problem (like repeated click-unclick would be). The top half of the case has plenty of room for a screen cleaning cloth (included) and a few SD cards and some earbuds. You can *JUST* fit two extra AA cells in the case, one on each side of the system. Playing games with the system still in the case is doable, as long as you don't need access to L and R very often (they are reachable, but not comfortable of course)
http://www.circuitcity.com/ssm/Pelican-Tra...roductDetail.do
http://www.circuitcity.com/ssm/Pelican-Tra...roductDetail.do