Newton Adventure is a free and open source 2D platform game. You play Newton, a very special hero who has the power to change gravity direction.
Newton Adventure is a 2d platformer with rotatable levels. This Windows installer allow to install and play Newton Adventure on Windows XP, Windows Seven and Windows 8.
Played this game and it's quite fun!
Made a video of it as well!
Youtube.com
It's live in about 40 minutes if you care to check it out!