Jason Fried hits the nail on the head regarding the current state of office productivity in this TED Talk (embedded below). Namely, interruptions are shredding our work days up into tiny 10 or 15 or 30 minute increments during which we are expected to get meaningful work done. Obviously, this is far from ideal. Towards the end of the talk, he offers some recommendations–my favorite being the suggestion of canceling the next meeting on your calendar.
Also, there’s an interview with Jason on the Big Think site that touches on this subject, among other things.