Fit out the stage for theater productions.
A Production Assistant (PA) is assigned to one particular area of a television or film set as a general helper. The job of the Production Assistant is to tie up loose ends, which usually means taking out the trash and looking up scheduling questions.
On set the Production Assistants are divided onto Office PAs, and Set PAs. In the first category you spend your time in the production office answering phones, receiving deliveries, and placing lunch orders for higher staff. In the second you are assigned to a particular division in the crew. This might be a department or a single actor. Production Assistants might demonstrate similar levels of busy work in fetching lattes, working with the Grips to prepare the set, and locking down the set to make sure no Extra comes on accidentally.
This is not a particularly wonderful job—you are the errand runner and grunt worker who gets paid very little if at all. But you do get to work closely with various other members of the crew. Given how competitive the film industry is, this exposure could do much to help your career advancement. So this is a great position if you can use it as a foot in the door to make connections.