I recently downloaded an XBOX Live Arcade demo called N+. The game is a 2D platformer that puts you in the shoes of a ninja with some serious hops that searches for gold and keys to glowing door. Originally build as a flash game, N+ has landed major cross platform deals starting with the XBOX Live Arcade version and development for both the Nintendo DS and the PSP. Once I played the demo, I had to buy the full version. Growing up, my friend Mike Murphy had a Commodore 64 (yes, with 5 1/2" floppy discs) and we loved a game called jumpman.
Jumpman was a Donkey Kong knockoff game and it had simple, addicting gameplay. Fast forward a few years and Nintendo kills the C64 and Jumpman can't match the style and appeal of Mario... the rest is history. Fast forward 25 years and we have N+, similar to jumpman, but a ninja. N+ sports an amazing physics engine, mad style and addicting (jumpman-like) gameplay.
You can waste valuable studio time and download the flash version HERE or give the demo a spin on XBOX live.