Years ago I ran a D&D game. As usual all the PC's were in the local watering hole. A dwarf (I think) comes up to them.
Dwarf NPC: Excuse me gents, would you care to go on an adventure? (Ok, so I wasn't too inventive)
PC's in unison: NO!!
Dwarf NPC: Aw c'mon guys...please?!?
Another amusing moment...
GM (me): Ok so you do (dice roll) 8pts of damage * 6 (head shot)...hey...what's 8*6?
Pete: Lots!!
During a superhero game...
GM(me): Ok, so he falls to the floor with a resounding thud...uh, Chris what are you doing this round?
Chris: He's fallen to the ground? I get out and beat 'im in da' head!!