What we need:
- 1 soda can,
- Fill 1/3 of the can with water;
- Place the can on the table with a 40º degrees inclination;
- Try to balance it, you will be able to balance the can in a "falling position", if the can starts to rotate over the bottom let it rotate until it stops.
There is a position where the can stands in a strange equilibrium.
Exactly for the same reason the forks found the balance here.
Try this with other recipients and/or cans.