Not much seems to run in Classic. I use it for Kid Pix (still the best color bitmap program ever) but as for other programs...

MacDraw II: Displays a black screen in Tiger's classic mode.

Sim City 2000: Seems to work OK

Jeopardy: Seems to work OK

The Sims: The CD installs the old OS 9 version, use an upgrade pack CD and it will detect OS X.

Someone mentioned Apieron, I think they re-released the shareware classic for OS X. I've also seen Solarian II redone for OS X and I think StuntCopter got similar treatment.