A while back, I was working on a pixel-art style racing game. The pixel based physics proved hard to control and was scrapped, but the pixel based fails were fun.
This was a proof of concept. Experimenting with different game concepts. Like Hill Climber but pixel based. The crashes were a lot of fun, and the pixel based physics worked ok slower, and had some great climbing features, but ultimately at any 'reasonable speed' it would be bouncing all over the place, and be difficult to control. I have ideas to expand on this, but its biggest feature as of yet, was the epic car shattering crashes, in a pixel point of view.