Well, Zero.Wing has released a new game called PSP TRIX. Now I'd have a hard time describing this game, so the author has kindly provided an explanation - "A game written in LUA for the Sony PSP, based on The Matrix Trilogy and a rhythm - action game, without the rhythm! (or the action?!?)"
Try figuring out what that means! Or, you can simply download the game and check it out. It looks kinda nice.
The game might be a bit buggy. "This is the first bit of programming I have done in years so yes the code is a bit sloppy but the bottom line is its working so I am happy with it for now. I might try to clean it up if theres ever a next release." There's a lot more stuff planned for the next release.
For now, check out the first release. Although the game is made using Lua, you shouldn't need Lua Player explicitly since the game bundles it together.