I make the most progress on programming, design, and other creative work in the morning. I process email best after accomplishing one big item. For me, A 30 minute meeting destroys at least an hour of productive work time; context switching has a high cost.
I know these things about myself and try to mitigate any activities that trigger these “black holes” of productivity loss or momentum killers.
Don’t let your workflow be defined by your surroundings. Know how you work and defend the process that works best for you.