Thank you everybody...I guess a combination of actions to suit the crime would be the best way. Medusa, I was thinking the same...had I seen them actually hurting the cat, somebody would have to chain me down!

Kitty came back this morning for some more Meow Mix. I had the office window cracked, happily surfing the net with my back to the window when the loudest most devil raising howl came from Churchy at 5:30am! Seems kitty was trying to get my attention by sitting right outside the window and, as it turns out, Churchy is a howler when strangers appear! Scared the mess out of me, lol! He's the first howler I've ever had...all my other cats (there's been alot too) have been thumpers (hitting the window). So Churchy's howling and Dixie's thumping (Toby wasn't very concerned about the whole thing and watched from the hall) was enough to make me lose it for a minute and I flew out of the chair taking the keyboard with me but leaving all my senses behind...
Anyway, kitty seemed fine, even felt a little warm. I'm thinking that somebody lets him out as they get up or as they leave for work. I wish they'd keep him in, or at least put tags on him.

Since we don't know his actual name, we've dubbed him Moses.