I'm not sure how many are actually aware that the FAA's rules forbid a controller from doing anything not directly related to air traffic control. No books, magazines, browsing the internet, TV, cards to play solitare, commercial radio, personal phone calls... Nothing. Stare out the window at the runway lights, or at the sweep going around on the radar screen, that's ok.
On a tower with zero movements over an hour during the graveyard shift, I'm amazed anyone could stay awake without being into amphetamines
