Here are 10 really dumb things to attempt on the Underground.
1. Lick the pole from the very bottom to the very top without once removing your tongue. Share your tasting notes with fellow passengers: "Yes, I'm definitely getting lemons on this one. Lemons, and possibly salt and vinegar crisps".
2. Start a petty argument with the robot announcer. "The next station is Oval? Really? Because it looks decidedly cylindrical to me, you git."
3. Alternatively, every time the robot announcer says "the next station is...", shout "MACCLESFIELD" over the station name. This is really funny. Try it. No one will hate you.
4. Stand by the doors and draw a circle around yourself on the floor with a permanent marker. Declare this your sovereign territory and confront anybody who crosses the line.
5. Curl a turd onto one of the seats, then clean it up using a doggy bag.
6. Place a massive rucksack on the seat next to you. When someone wants the seat and asks you to move the bag, take out your hive of Japanese hornets.
7. Fashion a cape from old tube seat material. This is the ultimate camouflage. You can now sit down anywhere you like and nobody will see you.
8. Naked cartwheels.
9. Wear an excessively tall hat and spend your journey hunched over, grumbling about TfL's millinery discrimination policies.
10. Attempt to use a freshly harvested oyster to swipe through the ticket barriers. When approached for assistance, insist that you topped your mollusc up with pearls only this morning.
Please add to this list in the comments below. Or don't. See if we care.