I've had a fascination with maps for as long as I can remember. During family road trips to San Francisco I remember tracing our route on a map with a highlighter in real-time. Many, many years later, I am able to trace my route automatically with a GPS receiver on my phone.
I have been carrying a GPS tracker with me at all times for over 3 years, walking, busing, driving and flying. Below are images generated solely from the GPS data. There is no underlying map. The color of the lines corresponds to the speed I was traveling. Frequently-traveled paths appear thicker because of how many overlapping tracks there are.