Life Hacks are tricks, ideas, suggestions, and tools for making your life easier and for increasing your productivity. The Economist recently carried an article extolling the virtues of potential of Life Hacking (10th-16th June 2006). One example hack quoted by the Economist is to set your email so that it only downloads email every 15 minutes, or perhaps even every hour (I have set it to 20 minutes and I think it is helping). The idea is that you get interrupted less often and get on with you top priority task instead. Also, I have found that by downloading every 20 minutes I often get 2 or 3 related emails, for example one asking for help, a second clarifying the request, and third a reply from somebody else solving the problem - and I did not have to do anything.
More information on Life Hacking is available at Lifehacker.com and 43Folders.com.
One really useful post at 43Folders is Writing Sensible Email Messages, which focuses on how you can write your emails in ways which make it more likely that you will get the response (be that a reply or an action).