Ever since the beta for Littlebigplanet hit, there have been numerous level designs, some good, some not so good. From classic Mario remakes to re-imagining of the humongous spectacles found in Shadow of the Colossus. Heck, even 7 years olds are game designers in the making!

But simply from an engineering standpoint, I think this is by far and away the best yet. A user created a real-time working calculator that accurately adds and subtracts numbers. The level is said to use 610 magnetic switches, 500 wires, and 430 pistons. I didn't see what the big deal was until the camera panned up. That's when my mouth hit the floor.