I log all rides in my free iPod app called Cycling Log, but I have a commuting only excel file at work. In addition to speeds, I track hrm data and estimated gas savings.

Strava https://strava.com

I lost two years worth of data when an online program I was using upgraded and no longer supported the old files a couple years ago. I now use RideWithGPS and also write the mileage and elapsed time for each ride in a day planner.

3 x 5 spiral notebook and an excel spreadsheet. Spiral notebook boots up immediately, requires no batteries, hasn't crashed yet, and I learned the software in grade school.

Jan 1 through second weekend in June I track in Excel against a training plan to prep for the local BikeMS to be sure that I'm ready for the 150 mile weekend.

June through December I just ride my bike but do keep track via odometers on the bikes so I know what my total year's mileage is. However, I do not have computers on the mountain bike or single-speed because, to me, one of joys of those bike is not to worry about things like miles.

I use dailymile.com. Great site.

WKO+ for training. Strava for sharing / comparing segments.

I don't like keeping records of anything that will have to stand up through scrutiny later on.

Currently using a Google docs spreadsheet and Training Peaks. Manually adding new data in both places until I feel good about just using Training Peaks. Next week I plan to input all my training plans into Training Peaks for the 2012 season. Maybe Santa will bring me a Garmin 500.