As for the comments that cat should be kept indoor, well, i don't believe that. Not even the most psychotic anti-social would like to be prison indoor. Cats are naturally curios. So, i don't think it's humanly right to deny them their nature to roam around. Sorry, bird lovers.
I, myself, have 3 cats. 2 of them are quite cool and laid back. And by that i mean they are more like the lazy Garfield. They eat, they play and they sleep. That's it. And there is Frankie. He is a whole different story. A predator. A cold one, if i may say. He catches 1-2 birds a month, 1-2 frogs or rats a week, and lizards on a daily basis. And he always brings his loots home, and place it in the center of the living room, in a place that hard to miss, just so that he can show off.
That's Frankie and his prey.
Just so you know, he didn't killed the rat because i stepped in and let it escaped. I felt bad taking the rat away from him. Felt like a bully.