I do not know about you, but I am a very analytical person and really love very granular data. On my quest to implement GTD for myself, I came across a very cool open source tool called Manic Time (I am not sure if I can post a link here yet since I only have a few posts, but here goes: http://www.manictime.com/
If that does not work, it is just manictime with the www and dot com around it!)
It records every bit of your computer activity and tells you how much time you spent on what application (is based on ACTIVE applications, so you can have many programs open, but it calculates the time spent actually working in it) and then breaks that down by actual website, document, file, etc. that you have worked on in that program. It also compares the time spent over any given time frame. So now you can see, wow did I really spend 57% of my day in Skype? But I am only replying here and there to IM's - that stuff really adds up (I do not spend that much time on Skype, but you get the point).
It is very easy to use and you can also a button called "off the record" if you want to privately work on certain things...