Interruption Tax - the time taken to respond to an interruption (and believe me, with a 17 month old daughter I'm taxed highly on this point)
Interruptions are the bane of my existence lately, whether it is someone stopping by my office, the phone, new email, or my own brain deciding that I just have to check out that web link. On some days, I find that I have spent the entire day on interruptions and have gotten very little done of what I had thought was important. Frequently, the interruptions are interesting, but were they important? Back to the discussion of Urgent x Important.
When I recognize what I am doing, I have to step back and review what is important to me today. This is where the value of taking those 15 minutes in the morning to plan the day comes into greatest effect. Even a simple checklist of things I'd like to do helps me significantly.