The Tarahumara Indians play games based on running — passing a wooden ball from runner to runner for exampe — for hundreds of miles at a time. I’m not that hardcore, but I have found some ways to entertain myself while walking or running.
Running or Walking to Music
Load up your iPod with your favorite music with a beat of suitable pace, put it on shuffle, and go to town. It may take some experimentation to find music of the right speed for you. What I like about this is that it gives an interval effect — I speed up when the music does, then get a rest on the slower songs.
A car going the same direction I am counts +1. A car going the other way counts -1. This can be especially challenging on a four lane road where lots of vehicles might pass at the same time.
Where I live, if I wave, most folks will wave back at me. Some of them wave before I do. I think those count, too, especially if I wave back. Each time, I get a little hit of friendliness and warmth. It’s nice.
The best exercise is the one you’ll do. If inventing games will get me to exercise more, or keep at it longer, it’s well worth it. Have fun.