Puppeteer said:Super Soakers work a treat. If you see a cat, squirt it with a water pistol. You can even hit them from inside sometimes. The cat doesn't have a clue what happened, but they don't like it. They learn pretty quick.
The two kittens next door keep roaming our yard and stalking my guinea pigs. I have had hours of amusement shooting at them with a water pistol from the kitchen window. They leap about 10 feet into the air The best part is watching the stupid things trying to figure out where the water is coming from. They keep coming back, so maybe not a long term solution but it sure is good fun