a bottle (I recommend a plastic one, personally playing with the type used for tonic water though any long cylindrical object may work OK)
Your score is the length of the game. Longer times are better.
Before the game begins, place the neck of the bottle on the palm of a chosen hand, so the bottle is standing vertically.
Once the game begins, nothing may touch the bottle apart from the palm of that hand and the hand may only touch the rim of the neck.
The game begins when the bottle touches something else or is no longer in contact with the hand (usually due to falling over).
Time to play:
2 seconds-4 minutes
Constant immediate feedback - both visually and through touch.
Very 'juicy' - a tiny input (hand movement) has a massive effect on the game state.
Rapid/constant changes in game state. Results in constant excitement.
Several successive short-lived games can be demoralising.
Game lacks any progression - game state never progresses beyond where it may have started.