I'm a fan of the pomodoro technique. The idea is to use a kitchen timer, set it to something like 20 minutes, and focus solely on a single task until the timer stops. Extremely good for work that doesn't exactly yell " Yay! I'll be fun !"
The ticking is the constant reminder of focus and sets the mood from to a sort of "I'm now Jack Bauer sorting his inbox in 20 minutes to find the lost email with the map pointing to the location of the nuke in LA. While sipping tea."
Works every time.