If you haven't been reading the Bwog, Columbia University's newest and best blog, you are missing out. Case in point: their capture of this awesome billboard in Butler library. Get it? It's a play on "butt-sex!" Amazing stuff. Come on, NYUers-- you guys are sleeping downtown! Snap to it! [Semi-related: it's safer-sex week at Columbia, which means that the Health Services people are breaking out their collection of dildos and cock-rings. For real!]