See how long you can hold a note
(Amusement Potential: 4-20 minutes)
Not that much fun, but it sure passes the time. Play with a friend, or try to beat your own personal best. Inhale deeply and then try and make a noise for as long as you can. Earn extra points for making your partner laugh or ending on an amusing note.

Try to not think about penguins
(Amusement Potential: 1-5 minutes)
This is especially hard, because by trying too much, you remember what you were trying to avoid thinking of. If you try too little, you end up thinking about penguins anyway.

Use your secret mind power
(Amusement Potential: 5-10 minutes)
Pick a passing by and try to use your mind power to command them do something, like drop their bag or knock into someone. The law of averages dictates that sooner or later one of your mind commands will come true, so you can convince yourself that you really have super human powers and waste even more time trying them out.

Scratch yourself
(Amusement Potential: 1-3 minutes)
Go ahead, scratch yourself now. Even if nothing itches, go ahead. Doesn’t that feel pretty good?

Repeat the same word over and over until it loses its meaning
(Amusement Potential: 1-3 minutes)
Pick a random word out of a magazine and say it aloud to yourself until it becomes a meaningless set of noises.