For months we had a horrible roach infestation in my office (I mean HORRIBLE, like in the movie Creepshow). Our supervisor refused to address the problem for some reason. We didn't want to go over his head and involve admin, but we also didn't like risking bringing a roach apocalypse home with us everyday after work. So I asked security to get me lots of roach spray, for which he prepared an expense report that went straight to HR.
I'd like to say that once HR got involved, the exterminators were finally called, but that simply didn't happen. I befriended a director in admin; the exterminators were there the next day.