An acronym for the phrase "Shake my fuckin' PP." Used as a more severe substitute of "Smh," for when it's just not enough to express the sheer disappointment you feel at the target.
Guy: Yo, did you hook up with her or no?
Guy 2: I sent you a text earlier about that very fucking topic smfpp.
12 step recovery jargon referring to someone new who talks about how great life is, now that they'resober. Usually meaning that the person is out of touch with reality.
The new guy seems pretty happy for a dude who has no job, no money and no family. He must be on a pink cloud.