This was my entry for the Gamma IV competition. Still fixing a few things on it, will hopefully release it within the next week or two (after GDC).
In OB, you change the way your pixel moves, by holding/not holding the button, to try and connect other pixels together. There is a co-op mode as well where you and another player controls the same pixel. You can hit switches to stay on screen increase your score multiplier. There are also wave changing pixels that change your wave type, which can alter your opponents direction or speed.
Update: I now have it available for download at http://www.mediafire.com/?q0momzjt1zz
No sound though, will add if I get bored.