Been dealing with these things over the winter. I'm both glad and creeped out by having read this now. I have a method to kill them that works and doesn't smell, but is quite annoying - I shoot them with my salt gun a few times. The real key is to get a near-range shot to the underside. Sometimes It takes a number of them, but I can usually do it in 3. One to knock em down from their perch, one to stun, one to kill.

The salt it leaves behind is annoying to clean, of course, but I've found it to be quite effective.