When your teacher asks you what water is, and you start explaining that first you have to mix O2 with BOYL to get FOG, then, you use WHOL to pressurize the FOG, obtaining WATR. Need any more explaining?
When you report people to moderators for spamming creations on threads to get them noticed :P
But seriously... when someone asks to play football, and you accept, and you're shocked when someone kicks the ball: "WTF! No moving solids, you n00b."
i freaked out the other day when i saw my black rasberry ice-cream (very yummy) was purple, so i thought it was either going to release neutrons, explode, or slowly eat through my toung/turn my head purple :P