Frozen Bubble
Once dubbed the most addictive game in the world. It was originally written for Linux and spawn a whole host of ports and clones. The rules are simple: shoot bubbles out of the cannon to form self-destructing groups of three or more. If no more bubbles left, you win. If the ceiling falls on you first, you loose.
Angel-Bothorius
You're an angel on your way to work and you fall through a hole in the clouds, happens to everyone right? You lose all your feathers and get stuck on a wooden island in the sky, again, happens to everybody. Now you need to collect enough feathers to get back to heaven......well, good luck with that.