We used to be a company that did a traveling trunk show in Renaissance fairs (seriously). At that time, all of our props were in a burlap sack. So when it came time to name the company, it was called "SAK Theatre Company". S-A-K fit better on a business card and the wacky spelling was appealing to our founders. :)
No one knows. From what I've heard, it's actual lost knowledge. If it ever stood for anything, there's no record of what that was.
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