How about burning the building from the top floor down, floor by floor. Give them some oxygen tanks so they can survive until they crispy critters.
Crispy critters works for me. In fact, I wouldn't mind dropping a few nukes in the ME and having a whole bunch of crispy critters. See, I REALLY am a meanie when it comes to them. LOL
I think nuking is to nice! But is sure gets alot of bang for your $$! :)