'Member, werewolf is only dangerous to humans, and Voldy is at least nominally human.
I concede it'd probably take a lot of effort on their part (but they're brave boys and aren't afraid of hard work), but it strikes me as rather fitting. We know Voldemort cannot be killed by any spell. (At least, we think we know this.) So - what about not using a spell at all? What about descending to the most basic level of violence, one wizards probably haven't even touched on for millenia? Maybe that'd work.
And - well - if it doesn't, at least we'd have the pleasure of seeing Voldemort's head lying on the ground, shrieking, "Where's me body? WHERE'S ME BODY?"
**Chortles** Ah, I can see Book Seven sparking off an era of bookburnings that has not been seen since the Spanish Inquisition.