Cannon Blast - Burn your cannons rope and watch it shoot down those ships
Zelda - Another awesome flash clone, Play zelda in all its glory. Arrow Keys to move, ctrl to drop a bomb an
MegaMan Project X - You all know this one, now you can play this excellent platform game online!
Super Mario Crossover - Almost the same as the original Super Mario Bros., but with a special twist: now you can play not only as Mario, but also as Link from Legend of Zelda, Mega Man, Samus, Simon Belmont or Bill (from Contra). Each character has special abilities.
Escape - Try and escape by killing everyone! Simple as that :)