My shop serves several purposes. Primarily it's a place for me to build stuff. But one of it's important secondary functions is to provide a place of respite from the rest of the world. A place to go and forget about the issues of life and spend a few moments without worry or pressure or stress or trouble.
I occasionally enjoy going down to the shop and working on nothing. I may tidy up the place a bit, or make minor improvements to storage or organization, or perhaps just go down there and zone out for a few minutes.
Most times (by far) I'm working on projects, but I'd be lying if I denied it also provides a simple place to get away from the world for a few brief minutes.