A couple weeks ago I made chess for the ti nspire. Just though I would make a topic out of it. You play it using the mouse offered(I might change it to use arrow keys, possibly), and it is mostly complete. Some of the graphics aren't too great and it doesn't really check if you are checked or under checkmate, but other than that, it is done. I also thought I should point out that it is two player only.

Side note: I was planning to make an ai but I don't have time right now and wan't to just make more nspire games cause there is a deficiency of good nspire lua games right now(can't get ndless, my calc has os revision 4.0), maybe coming back and fixing them as I go along.