Not funny if the fan is metal. Plastic works best, because the blades usually spin faster.
Showing disdain by raising your thumb to your noise and wiggling your fingers. See also British.
You know you had to think about it.
Sometimes it's the only sporting event on. See also Basketball.
Kind sir, might you lend a hand and add a funny thing to do?
...or seafood paella. This will strike you as even more hilarious if you've actually done it. See also Alcohol.
Quite possibly the most pointless, yet funniest and most randomest thing to ever do. See also Hair.