Pinky, from the cartoon "Pinky and the Brain" would always say stuff like: NARF! ZORT! TROZ!
...I like Narf!, so....that was pretty much it.
EDIT: I also use 2Hit6 as my game handle in other games when ! isn't allowed or if Narf was taken. If you know Cantonese, then if say: "2" "Hit" "6"...