Do you know about the pomodoro technique? (Google it--everything is out there for free).

I can be a magnificent procrastinator and sometimes find it hard to focus. The Pomodoro technique has you set a timer for 25 minutes, during which time you focus intently on what you are doing. When the timer goes off, you take a 5 minute break. Then you start another 25 minute segment, another 5 minute break and so on.

Usually after 3 of these, I'm ok. It's a great strategy to have in your toolkit.