Acronym for White People Are Crazy. Although started by a white, southern, gay boy, it is a term used exclusively by black people when they are witness to bizarre or obscure events in which white people participate and/or caucasian behavior in general.
Orangello: "Did u c Jim jump off dat building n2 a dumpster? Dat's sum str8 ^ WPAC shit."
(Translation: "Did you see Jim jump off that building into a dumpster? That's some straight up WPAC shit.)