Interesting idea.
There's "The Mission is Fucked" from the Grey Wolves, and I can't remember it exactly right now but there's "When They Get Their Way, You and Your Kind will be Lying in the Gutter", or something like that, from a Con-Dom t-shirt.
In a lot of ways, a lot of PE lyrics are very sloganistic in themselves, in that they're usually just a few simple phrases declaimed strongly. I've always liked the GO track "It's Over", chanting that simple phrase a few times towards the end of the piece.