I don’t know if the dog dazer will make dogs run away with their tail between their legs or just annoy them enough to bite you but it’s a cool idea.

A must for walkers, joggers, and outdoor enthusiasts. Great training tool for dogs, too! Inaudible to humans, the Dazer emits safe-but-annoying ultrasonic soundwaves to keep unwanted canines away. Easy-to-use device includes belt/pocket clip or fits snugly in your hand. A great gift for police officers, meter readers, postal carriers, and express couriers!

I’m just waiting for the annoying teenager dazer to come out which would work in the same way as the mosquito ringtone but be really annoying instead of sneaky

Dog Dazer found via Book of Joe.