I had rats in the walls out in the garage. Saw one scamper into a hole near the breaker box by leaping from a shelf!
This means war.
Bought one of these babies at Lowes for about $5:
http://www.tomcatbrand.com/ratsnap.html
Quite a clever design. The bait comes in from the bottom, so your fingers never have to get close to the jagged jaws. It cocks and locks with one hand. The trip plate is flat and wide.
The first casuality occured within three hours of installation. Over the next week, I got three more adult rats, and a pair of juviniles (twofer!) Works very very well.