My main form of exercise is running (maybe better to categorize as jogging for some people). Every other day or so I run about 4 miles. I occasionally mix in a little bike riding, light weight lifting, or recreational swimming.

I noticed in the latest Road Runner Sports catalog (no easy URL) that you can now officially completely geek out your run with tools that track your vitals & time, listen to music, track your GPS location, display maps, upload all data collected to a computer for post analysis, etc.