a funny word derived from the term rofl (rollin on floor laughing). roflcoppter can be used to describe a helicopter that is in the process of "rofling" or just a helicopter.
when playing as Op4 in call of duty 4 online, one can yell into the microphone "TALIBAN! TALIBAN! SEND IN ROFLCOPPTER NOW TALIBAN!" and either you or a team mate would send in a helicopter to give cover fire. or, if there's an enemy helicopter in the air, you could say to a team mate with a bazooka, "TALIBAN! TALIBAN! THERE IS ROFLCOPTER TALIBAN! SHOOT DOWN INFEDEL ROFLCOPPTER!" once the enemy roflcoppter is destroyed, "AEI AEI AEI AEI AEEEEEEI!!!"