Here is any idea that i want to play with some friends....
You sit down and tie 1 ankle above the knee of the other leg, then stand up and try to stay balanced as long as possible.
To make it more interesting you can always try stuff like tie the persons hands behind their back or even if you are doing it at the same time, you could tie your hands together so you got to use teamwork to stay balanced.
Of curse, do it near to something soft, like a bed, so in case you need to fall you can always try to land on that instead of a table, chair or the floor.....
