ZOMG LAZER PEW PEW PEW 

an expression of... well nothign really, this is used by people who are excited and happy about something that is in most cases unrelated to the topic at hand.

GuyA: What's up?
GuyB: Nothin Much, How bout you?
GuyA: Ask your sister!
GuyC: ZZOMG LAzER PEW PEW PEW!!
GuyB: <GuyA's name here> fuck you, and <GuyC's name here> WTF?!?!?!?!!1

ZOMG LAZER PEW PEW PEW by FacelessWoWAddict August 28, 2008