My brother and I just posted a blog entry on Lugwrench Brewing about nanobreweries, based on some light-weight web research. The entry provides a really basic overview of nanobreweries, some things to think about when starting one, and some useful links. Check it out if you are interested:
http://www.lugwrenchbrewing.com/2010/03/nanobreweries-how-small-is-small.html
Nanobrewery Post