I started keeping track of my running & walking mileage in 2004.
I count any and all miles on my feet that I can record and obsessively add them to my spreadsheet. In addition to data from the Garmin or treadmill, I also go to gmap-pedometer.com and trace walks to dinner and any walking I do while traveling and site-seeing where I don't have my Garmin.
This week, I crossed a total of 10,000 miles since I started keeping track.
Those 10,000 miles have destroyed 20 pairs of running shoes over 7.5 years in 16 countries, and include 13 10Ks, 31 half-marathons, and 7 marathons (with another 10K and marathon coming up in the next 2 weeks.)
Not bad for someone who used to believe that they didn't like running.
I think it's safe to say I've changed my mind.