Best 2D platformer
Couldn't find a thread on this topic by searching, so I thought I'd better make one. Love the genre myself, and I'd love a few recommendations. I know there are threads online, but I've mostly been disappointed by the games I find there that I haven't already played.
My own top picks would be, in order.
Castlevania: SoTN (psx)
Super Mario World (snes)
Cave Story (PC freeware - go get it!)