Knowing how much time you spend on your computer: TimeSprite

Mike Gunderloy blogged about TimeSprite. I downloaded it and thus far the results have suprised me. 

Group your items into something like "Email", "Development", "Internet Personal", "Internet Work", use it for a few days and then look at the #'s.  Almost 20% of my day is spent in Outlook and only 35% is spent on Development.