As someone with perhaps more than my share of obsessive-compulsive behavior patterns1, I have always engaged in various informal personal challenges when it comes from getting from one place to another. In my younger years these typically revolved around exact routine and/or counting. For example, one long-running challenge was to make the number of steps in my walk from home to school an exact power of four. There were numerous rules to this challenge: The starting and ending points were exactly determined (threshold of the front door of home, threshold of the school door). I also had to proceed with a (fairly) uniform stride throughout (no giant steps or baby steps to artifically reach a target), although this rule was somewhat flexible in that I could walk faster or slower (but naturally so) in order to maintain a uniform stride. I also had to proceed "directly", rather than taking any detours solely for the purpose of adding to the step count (I allowed myself to select the angle at which I crossed streets, but in practice the route only allowed one such decision as it was a fairly straight shot). Finally (and perhaps most importantly) I had to keep the challenge secret from others. That wasn't so hard; my attention to walking may have been noticed, but it was easily disguised as a (childish, I thought) attention to avoiding stepping on cracks (which, by the way, offered an excellent means of assessing and controlling stride length). Sadly I have no memory of how well I did (even though I remember keeping track of my day-to-day performance on graph paper), but I'm sure I did quite well.
Nowadays, though, I'm very different. I do occasionally count my steps, but not for personal challenges! Instead it provides a good answer to questions like "which shop is closer?" and "exactly how much further is it to walk than to take the bus?" and "how many steps is it to the pub?" (errrrr, scratch that last one). But I do occasionally participate in challenges like those of my youth, and I'm happy to say that I completed one today. This challenge is bicycle-related and can be described very simply: Ride to work without touching a foot to the ground. Of course there are many fine-grained details: it's ok to MOMENTARILY come to a stop and balance, but only MOMENTARILY. Trackstands (and their ilk) are considered cheating. It's also not acceptable to ride in circles or loop back and forth to wait for a gap in traffic, and definitely not acceptable to do things like riding up onto the pavement (sidewalk) to avoid a line of traffic, a stopped vehicle, a traffic signal, etc.). Due to the many different reasonable paths from home to work, however, I did allow myself to take alternative routes to achieve this challenge (it's best to avoid high-traffic routes unless they have few traffic signals, definitely wise to avoid areas with lots of pedestrians, and the fewer crossings of major streets the better). Well, today I completed the challenge for the first time from my current residence (even though I still needed to take several blocks' detour around police cordons). This means I can lay the challenge to rest, at least until I live somewhere else. It's pointless to consider more difficult alternatives (getting to work without braking? Far too dangerous and practically impossible; I braked at least thirty times on my way here) so I have a feeling of (very minor) success.
1Pulling up my knee-length tube socks until the tops frayed to death, pushing up my glasses continuously, counting for the sake of counting, creating histograms of surnames by frequency in the telephone book, memorizing from the (1976) Guinness Book of World Records, and many more. Good thing I married a "checker" and not a "counter".