My favorite platformer ever is easily Kirby's Canvas Curse on the Nintendo DS. Canvas Curse was the first game on the DS that did touch controls right, in my opinion. Not only that, but behind the great controls was a phenomenal game with a lot of depth.
With that said, I haven't spent nearly as much time playing Canvas Curse as I have playing Sonic & Knuckles. S&K is my second favorite because I love turning Super Sonic, and I still question whether I've found all the Super Rings in the game yet. Oh yeah, and because the final battle with Robotnik as Sonic is EPIC, and fighting Metal Sonic as Knuckles is equally epic. Most platformers fail to be epic, they only manage to be a lot of fun.
Currently playing: Uncharted: Drake's Fortune, NBA2k11, Metal Gear Solid, Picross 3d
