Merlin Mann is advocating a lean process to deal with our flood of emails and become more productive: http://inboxzero.com/video.
The talk itself is 1/2 hour (~2:30-32:30), the rest is intro and Q&A.
The basic idea is to keep your Inbox empty and not spend time re-reading and re-considering emails without responding.
What I like about it is that you can apply the Inbox Zero principle to other tasks: get each new task out of your mind immediately by either getting it done right away, scheduling it, or deciding not to do it. In other words, get a system that helps you NOT think about any other tasks than the one you’re working on right now. This will reduce decision fatigue and help you focus.
“That Zero? It’s not how many messages are in your inbox – it’s how much of your own brain is in that inbox.”
— Merlin Mann