Chrono Trigger still gets played.
Chrono Cross, not so much.
Diablo 2 still gets played but for some reason it won't let me online.
MEGAMAN... of course. All of the initial series and X 1-3. I wish I had Megaman Legends 1 and 2.
Super Mario Bros 3 is just as fantastic today as it was when it released.
I also still play the Zelda games.
So many from the ages gone by are timeless. Today's generation can't really claim the same.