I work in a shared office building, and I take a laptop with a self-contained test environment into my day job. I then spend lunch working in a quiet room elsewhere in the building with no internet connection.
It works well for me because I'm awake and thinking about tech problems anyway thanks to the morning, and an hour with no distractions is enough to make small gains.
This is a useful trick in situations where the image changing under your feet isn't very important.