...that is, if you find a GameCrazy that still has any "classic plastic" in stock.

As expected, the one I was at today mostly had sports titles, but I found some decent stuff (all cart only):

Genesis:
Buck Rogers: Countdown to Doomsday (R4)
Eternal Champions
James Pond II: Operation Robocod
Tecmo Super Bowl II: Special Edition (R5)

Game Boy:
Blades of Steel