Zero Gravity is an maze type puzzle game. You simple help the driver get into his space ship. Sounds simple, but some levels can be quite a task. It is free! Give it a try.

Zero Gravity was produced in just five weeks.  There is a video interview on Microsoft's Channel 10 about the process:

http://on10.net/Blogs/laura/zero-gravity-silverlight-based-puzzle-game/

And a bit more information at:

http://zerogravity.terralever.com/

Zero Gravity is a easy to understand maze type game.  You have the drive someone on the screen with walls and other objects blocking his way to the ship.  You simply guide him to his ship and you are off to the next level.

While that sounds easy enough, when you move a directory, you continue to move in that direction until you hit an object or fly off in space.