When I shared a house and was leaving the house empty except for our pets, I'd always yell, "See y'all later!" This was in case anyone thought I was leaving an empty house, as we lived in a rather dodgy neighborhood and the house next door was broken into the day I moved in. I had a dog, but she was a total marshmallow, although she would bark. Must have worked - we were never robbed.
I do like the idea of putting a huge dog dish with "Killer" painted on it on the front porch to discourage burglars. Since all of my neighbors have dogs, it's hard to tell exactly where the barking is coming from, and the dogs next door are large and sound like it.