Movie filming in ATL question

I can't remember if it was this board, or another one I read, so if it wasn't this one I'll delete. But someone posted about a week ago about them (or their company, I guess) posting red signs all around town that had something to do with filming. The signs say "Sic 'Em" and have an arrow on them. I saw one this morning and was just curious. Does anyone remember seeing that on here, or am I thinking of another board maybe?