Surplus Department. Huh?

The sign on the door reads "Surplus Department", and I'm sure that in the organisational structure of the company it has a specific meaning, but it seems strange at first glance.
Is this just an example of nepotism and everyone employed by the department has been given a meaningless job because of "connections" or influence? I hope not.
Are the employees in this department just waiting to be "downsized" and are being kept out of the way until then? The mind boggles. Perhaps its a charity that distributes a surplus? Any other suggestions?

P.S. I will try to get a less shaky picture. Too much coffee, I think.