I hadn't heard the term "commonplace book" before, but it sounds like a perfect description of the "outboard brain" - the main reason I started blogging. It wasn't about publishing anything, or discussing or commenting or connecting. It was documenting a flow of ideas and contexts.
Steven Berlin Johnson gave a talk back in April, describing the history of the commonplace book. He was using it as an introduction and context for the need to be able to remix content - as an argument against locked down electronic books that implement DRM to prevent copy and paste - and it nicely describes both the need to remix, and the need to document.
Scholars, amateur scientists, aspiring men of lettersâ€”just about anyone with intellectual ambition in the seventeenth and eighteenth centuries was likely to keep a commonplace book. In its most customary form, "commonplacing," as it was called, involved transcribing interesting or inspirational passages from one's reading, assembling a personalized encyclopedia of quotations. It was a kind of solitary version of the original web logs: an archive of interesting tidbits that one encountered during one's textual browsing.
Interestingly, he mentions a historical precedent to multitasking and attention deficit reading, citing Robert Darnton:
Unlike modern readers, who follow the flow of a narrative from beginning to end, early modern Englishmen read in fits and starts and jumped from book to book. They broke texts into fragments and assembled them into new patterns by transcribing them in different sections of their notebooks. Then they reread the copies and rearranged the patterns while adding more excerpts. Reading and writing were therefore inseparable activities. They belonged to a continuous effort to make sense of things, for the world was full of signs: you could read your way through it; and by keeping an account of your readings, you made a book of your own, one stamped with your personality.
Johnson's full post is well worth a read (go read it now, if you haven't already - he goes into the implications of DRM for eBooks (both implicit and explicit forms of DRM).
But the idea of a commonplace book resounded with me. I see my blog, primarily, as serving that role for me. That's why I started the blog back in the olden days. That's why I keep posting stuff to it. And why I posted copies of coursework and notes from the grad program. It's all part of a narrative, documenting various contexts.