"I feel like a house-elf," grumbled Ron [general cleaning of Black's house] "Well, now that you understand what dreadful lives they lead, perhaps you'll be a bit more active in S.P.E.W!" ... "You know, maybe it wouldn't be a bad idea to show people exactly how horrible it is to clean all the time -- we could do a sponsored scrub of Gryffindor common room, all proceeds to S.P.E.W, it would raise awareness as well as funds --" "I'll sponsor you to shut up about spew," Ron muttered irritably."