The Gomboc is the world's only artificial, self-righting shape:

The Gömböc doesn't have any power, and is a consistent weight all the way through. It has a wide curve on the bottom, surrounded by flat-ish sides and a ridged curve of a top. No matter how it's placed on a flat surface, it will right itself. It's what's called a mono-monostatic shape, and was born of mathematical theory. The theory stated that a self-righting shape was possible, and that it had one stable point of balance, and one unstable point.

Placing it on the curve on its top will let it pick itself up quickly. Placing on its flat side starts a slower process. It rolls back and forward slowly, then slows almost to a stop, then rolls back and forward quickly in a tiny vibrating motion, and then falls onto its stable point of balance, righting itself again.