On: Fair coins tend to land on the same side they started

[matteoraso]

I actually used to be really good at manipulating this as a kid. Basically, if you toss a large coin with a stiff arm, you can get it to flip exactly 1 and a half times before you catch it. I would always use this to win bets with my friends.

[gowld → matteoraso]

If you are allowed to cheat, you can also spin the coin to not flip at all.