I made a little falling sand game for the TI-82 (and other calculators).
It's pretty slow, as it's written in TI-BASIC, but I think it's pretty much playable.
Currently, it includes three types of particles (brick, sand, sand generator), but I'll probably be adding more soon.
The features include an edit mode (pausing the simulation) and a temporary fast mode that makes the simulation a bit faster while sacrificing the controls.
The attached GIF is at 4x speed, didn't I tell you that it's pretty slow?
The controls are described in the README.txt file. Also, included are the .82g and the .8xg files.