I had left this in a comment over at the blog of our Precentor of Measurements, but I thought I'd repeat it here. In the process of thinking about why I am writing this blog and what I've gained from it, I was struck by the similarities between it and keeping a laboratory notebook.
In science classes my teachers insisted on having us keep a lab notebook that recorded everything we could think of so that experiments could be reliably repeated or changed to assess the effects of certain variables. In a way, that's what this is. Life's lab notebook.