Zone Gadget

The Gomboc – Self Righting Rock

Looking at the picture, I think it is just a very simple rock, but it is not, the Gomboc is in fact a an Scientific Rock that also called "Self-Righting Object". According to wired:

The Gomboc is the end result of a mathematical theory, which stated that a
“mono-monostatic” object was possible, and that this object must have one stable
and one unstable point of balance. After ten years of work, detailed design
programs, and hundreds of tests with rocks of different types, the scientists
proved the theory right and the Gomboc was born.

As you can see in the video below (which compares its properties to
that of a turtle's shell), the Gomboc goes down on one of its sides, then
shakes, and picks itself up without anyone's help. The physical solution to the
theory has garnered the two main scientists, Gabor Domokos and Peter Varkonyi of
the Budapest University of Technology and Economics, several design awards and
the respect of obsessive geeks everywhere.