For a few years already I keep track of the rides on my racing bicycle on the computer. I like it to see how much I have cycled at the end of the year (or sometimes not, when it is not so much). And since I cycle to work in the summer, I also keep track of those trips on the computer.
But since I have more than one computer now and some of them run both Windows and Linux, I got a bit annoyed by the fact that I also had to load that one computer to enter the data. So I started to look around for some better way to keep track of my rides and I found this nice website, MyCyclingLog.
I am still in the process of putting my old rides on there as well, but I like the fact that I can now see and enter my rides from any computer and from anywhere. This is my profile, but I should not tell you this actually, as then you can see that this year I have hardly driven on my racing bicycle or cycled to work. Hopefully that changes soon as the weather improves again.