'Is that a spider?' RvB reference in Gears of War for sticking people with grenades. If I recall correctly anyway. Laughed my ass off whichever game it was.
There's one challenge (kind of like achievements) on call of duty 4 I wasn't even aware of, another one I'm a little hazey on, I believe you had to shoot through a wall and kill an enemy by hitting an explosive device. I unlocked maybe 4-5 challenges with that one shot too.. "Claymore," "Clay More," "Backdraft," etc.. Really wild scoring 2000+ points in a single multiplayer match.
A lot of achievements you get in dead rising. I was determined to knock down ten zombies with a bowling ball just because I bowl, I was totally unawawre of the achievement.