Darl181 has recently finished and released his
TI-83 Plus Axe port of
Maxwell's Demon, a game where you use an hole in a wall to sort white and black balls in their appropriate room. It is also possible to play with 3 or 4 rooms instead. With 3 rooms, the game features 3 levels of grayscale and with 4 rooms, 4 levels.
You can download it
here.
The author is also working on several other games such as an Aspirin clone, Space Run, a TI port of
The World's Hardest Game and others, that can be found and discussed
in his topic on the forums. Several are already available for download there.