I've got one of those Scarecrows, and it works like a charm to keep the birds off my lychee tree. Sadly, there are so many moving leafy plants around my pond that it would be constantly going off when there's any wind. Water's really expensive here, so that wouldn't do.
I've set it up in the back driveway a couple of times to try to discourage raccoons, but then the cat comes in wet and in a total huff.
It works fantastically to keep the neighbors' dogs from visiting, though.
