Petri Purho of Kloonigames has a reputation for churning out experimental prototypes in a matter of days. In 2007 one of these prototypes was the sandbox-style puzzle game Crayon Physics. The premise was simple — use a "crayon" to draw shapes that immediately come alive and interact with each other, the ultimate goal being to collect a star somewhere on the screen. The experiment was a hit, and soon it was announced that a full-fledged version of the game was in the works: Crayon Physics Deluxe.

Crayon Physics is one part Armadillo Run, one part Line Rider and tasks you with guiding a ball through a handful of stages by drawing shapes with a crayon-like cursor. Because of its rapid development time (five days), Crayon Physics is a bit rough around the edges. But this downloadable title is stuffed with creativity and shows that with a good idea, anything is possible.