Background Processing

An interesting side effect of writing side project code every day is that your current task is frequently running in the back of your mind. Thus when I go for a walk, or take a shower, or any of the other non-brain-using activities I participate in, I’m thinking about what I’m going to be coding later and finding a good way to solve that problem. This did not happen when I was working on the code once a week, or every other week. Instead that time was consumed thinking about some other task or, usually, replaced with anxiety over not getting any side project work done.

— John Resig, Write Code Every Day