Kitty Visitors

I now have two cats that aren't mine coming through the cat door and hanging out in my kitchen. This morning, I thought Orion was being a little weird, but figured he just wanted to be fed. When I finally got up and went through to the kitchen, there was a cat, with the color/markings of a Siamese, but with longer fur, crouched down on the kitchen floor. I hissed at him, he ran, and Orion puffed up all his fur and ran after him. Yeah, thanks for the help there, "Mighty Hunter."

I gave Orion some food, and took my morning shower, made coffee, then hung out on my computer drinking my first cup of coffee of the morning. With the first cup of coffee drunk, I put on some clothes (that's right, nekkid computer usage), and went back into the kitchen, only to chase off ANOTHER cat. This one is known as "Bad Kitty," although I think her name is actually Sneakers, and looks a lot like Orion at 50% of the size. I'd seen her in the house before, and the other cat tried to stick his head in when The Fat Man and I were watching TV a few nights ago.

I'm starting to wonder just how many cats I'm feeding. Is my kitchen turning into Cat Party Central at 3 in the morning? So, anyone got any hints or tips on keeping unwanted cats out of a house, while still allowing the wanted cat to come and go as he pleases?