The happiness experts say you should buy experiences and not material goods. I can't arrange to have experiences like this often, so in order to get my money's worth an important part of my task is to form memories of the day. It pains me to think how many of my days leave not the slightest trace in my memory, though I am thankful that at least I don't have many painful memories.

A GPS record of my progress is helpful, and I also take down some notes at the end to help jog my memory when I eventually start putting together a report like this. The job is made easier by my hope of making it into a good story rather than an accurate one.

"Just one single task" is almost a fantasy. Getting things done is satisfying, but to me it's an impossible challenge to be organized and motivated enough stay ahead of life's routine demands. Working on any one task necessarily means ignoring others. So on top of everything else one senses the additional duty to seek balance and peace. You can't win! Having just one goal for twelve hours straight feels amazingly simple and liberating.