If you really want to keep your monitors calibrated I would suggest a hardware calibrator as well. I just recently picked up the Pantone Huey and it automatically calibrates the monitors.
It's fairly inexpensive, and it works very well. I would definitely recommend it to anyone who does graphics, etc.
Thanks, ID! I've checked out the reviews for this product, and it seems like it's a good product. I'm going to check it out. I work with photographs and print design on a daily basis and so far I have not been able to find an affordable calibrator that I liked.