One of the freeing things I have implemented is what Merlin Mann calls Inbox Zero. It is a practice of zeroing out my email every time I check it. It does not mean responding to every email, but it also does not mean just leave it be. Instead, it is a series of decisions about what action needs to be taken based on this email.
Below is Merlin talking to the folks at Google about how to tame their inbox.
I have tried a number of Getting Things Done (GTD) tools in an attempt to make it easier to bring my box to zero. The one that works for me is a Firefox add-on to be used with Gmail call GTDinbox (now known as Active Inbox). The program integrates with my Gmail and provides me with read to go labels for emails. It makes it easy to decide on an action and to find the email later to take action.
It is so satisfying not only seeing that my inbox is empty, but that I have either acted on the email or sorted them into the appropriate places for action or reference. It is like removing a popcorn kernel from my brain.
Below is a sample of David Allen’s book:

