It was really too easy.
If you made the later levels longer, and made it so you couldn't hug the edges of the walls, you'd have a great game. Maybe make the wheels rotate faster as well.
Quite the good game, with a damn good song chosen.
Simple gameplay, yet effective. Maybe make a sequel with different modes, like moving your mouse left could make you go right, or just powerups or similar.
Leave a classic mode though. :D