Well, guess I've been lucky. Cats not a huge problem, I know a cat -can- kill a chicken, but I have hardly any neighbors and it sounds like those are the worst kind of cats. Also, since I am able to have roos and enjoy having them, they are quite protective.
My lazy house cat watches mice run across the kitchen floor, chickens are out of the question for him. He WILL chase the occasional stray cat away though. Also active semi-free range, (lot-range?) chickens including the alert roos and bossy hens, also seem to keep cats at bay...
A long long time ago I had a semi-feral cat come live outside, and I loved him cause he kept mice and probably rat populations down, never bothered the hens, they seem to have an 'ozone area' that the cat respected, soon they ignored him too.
I got him his shots and fed him a bit, he had a safe place to sleep and kept away the vermin, I think he kept opossums away too, and I hate possums, (please don't preach to me about all gods creatures
blah blah blah... they're nasty belly eating vermin
) I usually get some but when he was alive, NEVER. Good trade with the cat I'd say, but I was probably lucky.