Usually after I've finished coding some particular piece or resolving some issue, I take a walk out to our back entrance (we have a decent-sized landing near our loading docks) or just take a lap around the warehouse area.
It got to the point where one supervisor quipped: "I can tell when you've got some heavy coding going on because you start wandering by my office."
There are other times when I just stare at a couple blank files in whatever IDE I'm using or just lean back and stare at the ceiling.
I remember reading a series of kid's books (or maybe they're called Young Adult Fiction these days) where this gang of kids would solve some mystery or other. There was one bespectacled character who would lean back in his chair against the wall, put his hands behind his head and stare off into space. All the other kids would wait in dead silence until the front legs of his chair hit the floor again. At that point he had "the plan" all thought out and they'd run off and solve the problem.
I always thought that was the coolest character and in a way, I'm him , now...
Just my $0.02 from over here in the cheap seats of the peanut gallery - please adjust for inflation and/or your local currency.