I think Callie had sent out a cat-equivalent of an APB that my house is the place to go for birds and anything else.
Over a half hour ago, I just happened to look out the kitchen window to see if I needed to refill the bird feeder. Instead of seeing birds and/or squirrels, I saw a black cat walking across the deck, from where the feeders are to the sliding glass door. I waited a few seconds to see if it would reappear, or if I'd hear commotion from Zim downstairs, but neither occurred. I decided to go downstairs and investigate. To my surprise, Zim was sound asleep in his crate and the black cat was no longer by the sliding glass door. At this point, I figured that I might as well go and fill the feeders since I'm already downstairs, and to also check out if the cat was looming around somewhere else; it wasn't.
Instead of seeing Callie again, I saw someone new (well, not all that new since I had seen this black cat during a snow storm, walking down the street to the construction trailer).