I was reading an interesting article on eHow about keeping track of your travels around the world. My world travels are limited enough, that I don’t have to go to a lot of effort to track them. Besides Australia, New Zealand, England, Scotland, Wales, and France, I haven’t traveled widely. My trips around the U.S. and Canada are fairly extensive.
Perhaps you travel a lot, then you’ll want to read this and try out the method for tracking your trips.