I have two thoughts:

-- I would like to simply to get the lay of the land downtown, the Valley, and, maybe, Sonoma, maybe scout out the universities my kids might be applying to later. This is a very easy, low-risk way to fill the time. Here's a tentative collection of destinations: http://goo.gl/3DXqs. If you would like to suggest something, I would love to hear it.

-- A more intriguing idea I was toying with was to offer to meet with anyone exploring medical, military, disaster response, educational, or parenting start-ups. Not that I'm so awesome, or have any money, just a 35 year-old, married-with-kids, military doctor who happens to have some years of experience in each of those fields and will be the Bay area with nothing to do for a couple days and would love to meet some of you. I also worked on the team behind a content management system for medical schools after Hurricane Katrina (tmedweb.tulane.edu), and have done some design consulting/hacking work/interning (nic.org, edwardtufte.com).