CactiGuide.com

The late Paul Harvey, had a friend that lived in Lamesa TX. The man grew Cacti. He had a cactus in a pot he was holding, a man came and was threating him. He threw the cactus at the man, who took off. The rest of the story is it worked better then a cat.

It probably ruined the cactus, though, a cat would probably fare better. Though, I think a cat would be harder to throw accurately than a potted cactus. I guess it depends on technique and the cactus species.