I think for me the biggest thing I've found is prioritizing when tasks pile up. I don't agree with the 'task-switching' notion. I think if you have three things that need to be done in the next fifteen minutes, you should prioritize which one is the most important and go until you get it done. This is assuming that all three tasks can actually be done in fifteen minutes. If they can't, then it sounds like you already backed yourself up and you're too late, or you need to delegate some work out until you have time to focus on and approve each individual task.