Excerpt: Indie game-maker Petri Purho works in short, fast bursts. His blog Kloonigames hosts many examples of his rapid prototypes—experimental games whipped up over the course of a week and distributed free. The idea is to get something done rather than spending months or even years planning a project that never goes anywhere. When an idea clicks, like Crayon Physics , Purho invests more time in expanding upon his success. His latest off-the-cuff creation is Post I.T.