We don't kill them in this house, though we used to in the house we were renting in Somerville (they trapped themselves in our bathtub and none of us could bring ourselves to rescue them, so we would toss our hunter cat in there for five minutes and afterward wash the legs down the drain). I've only seen them twice here, but it's a 130-year-old house -- I expect they're just better at hiding than the ones in Somerville. We're in the middle of our yearly attack of those horrible Austrian cockroaches -- we literally see them walking up the front walk, and liberally blame the apartment building across the street (we never see them any other part of the year; this year is worse than usual, as they've set up shop in the yard more aggressively than usual) -- and I was heartened to see one of these things trireming its way across the living room. Go git 'em, buddy!