A community around these small handhelds such as the GP2X Wiz and the Dingoo A320 [0] has sprung up over the past couple of years. These small devices are cheap (about $100) and typically made in China somewhere. They are almost exclusively used to run emulators for classic games.

The OpenPandora is basically a response that the existing solutions (such as the GP2X Wiz) just aren't that great (which is true, I have a Wiz and I really don't like it). The OpenPandora will almost exclusively be used to run emulators, a smidge of web browsing, and that's about it.

[0] http://www.youtube.com/watch?v=-33IdcH3Wb8&t=6m36s