What surprised me by my plan was just how conspicuous and social my working area turn out to be. It helped that I was doing something peculiar -- who puts *sticky* notes on a white board, much less 50 sticky notes? I had at least a dozen people drop by and ask me what I was working on. It was great! I chatted with: two people I know from my puzzle hunt gaming circle; someone whom I met at KDD a few years ago and who hired on a couple of months back; my group VP; a grad school friend; someone in my training class last week; my mentee; and several other people.
I wasn't as productive in those hours as I would have been in isolation, but it was a great way to spend the afternoon. I need to practice this schema again. Having some physical-world work is key, though; just working on your laptop isn't inviting to passers by. It also was cool that I stayed away from e-mail and IM for the afternoon, for *that* reason I *was* more productive.