A shortenened form of the phrase "fuckin pisses me off". Usually said when the user is so pissed that theyforget to say the word pisses which adds to the vulgarity of the phrase which in turn, emphasizes the anger of the user.
Passenger:Hey that guy in the yugo just cut you off and now he is giving you the finger.
Driver:That really fucks me off. Hand me my gun.
Joe:Dude thatsucksthat your new car just got keyed.
Steve: Yeahthat really fucks me off.