After adopting him as a stray about a year and a half ago, our half-witted cat Harry has been bolting for any open door he sees for a couple months now. This is new behavior for him this year. I am fairly certain that Harry couldn't find his way to the front yard from the backyard - he's that dumb. But since he is declawed and really clueless, I do chase him down and plop him back in the house instead of just letting him do his thing and hope for the best. Normally, he does one of two things - he either tears around the house for the backyard and the bushes or, more frequently, he runs over toward the front door and then lays down on the sidewalk until you pick him up.
Today he bolted out as we were leaving to run some errands. He headed for the sidewalk this time, and had just started to lay down when he saw two squirrels in the yard and he was off like a shot after them! I had never seen him do anything like it! He was about 7 feet off the ground, up the tree after them, before his momentum ran out and he realized he had no front claws and had no idea how to use his back claws ... and so, gravity being what it is, down he came. He stood frozen at the base of the tree, staring at those fat squirrels, who were barking at him like crazy! I was actually a little leery of approaching the tree to fetch the cat, since mad squirrels are nothing to mess with and they were making such a racket. And I laughed and laughed. Unfortunately, no-one else had come out of the garage with me, so I was the only one to enjoy the spectacle and the others just had to be satisfied with my telling them what happened.
Reminded me of my former cat, Cricket, who was an indoor/outdoor cat when I lived in Seattle. I had this little backyard with a wooden fence, and Cricket loved to walk along it. One day, as I watched from the window, she was backing down the fence for some reason, right toward a squirrel, who didn't seem to see her either. And Cricket actually bumped right into the squirrel - they both went straight up on contact, and both shot off in opposite directions just like cartoon characters. I laughed awfully hard that day too - Cricket was a very proud cat and she did not appreciate my reaction.