Watching incredibly low-brow reality TV: Big Brother, Alone, Survivor, Project Runway.
I used to feel guilty about it, but at the end of a really taxing mental day, it's fun to unplug by watching a wide variety of people solve soft skill challenges. It puts my own problems into a different perspective. At the end of an hour or two of that, I walk away going, "Whew, I really love what I do, the community I do it with, and my family, because I'd fail miserably in an environment like one of those."