You can't make shit like this up. The new trolley service that begins in Seattle's old Cascade neighborhood is being called South Lake Union Trolley, or S.L.U.T for short. The people that run the trolley sure don't think it's funny (they call it the South Lake Union Trolley Streetcar or S.L.US which isn't a euphemism for a trampy woman, and thus probably won't catch on as fast). The people that live in the working class neighborhood are tired of being grouped in to "South Lake Union" rather then being called old Cascade, so it's only fair that they come up with a name of their own for the Streetcar.
The best part is that a coffee shop in the Cascade area called Kapow! Coffee is selling T-shirts that say "Ride the S.L.U.T"