Not going far enough

A long time ago I wrote a script about an inventor who invents, among many other things, a GPS device to put on your dog's collar so you can find it if gets lost or stolen. (This was well before the current GPS in every car craze.) I was tweeting with another author today who was on a walk and a friend's beagle pup broke her leash and was gone for an hour. That's a nightmare right there. Beagles are bred to run and find things, not stick by your side and they'll take off and keep going, sometimes for days.

Obviously my character's invention was only half the story. It also needs to include anti-grav capabilities so it can lift your hound and carry it back to you when you activate the device. Now that's a useful tool to have.