The last week of May is the Village Building Convergence (VBC) in Portland, OR. The annual event features numerous community build sites around the city, as well as workshops and evening community gatherings. http://vbc.cityrepair.org/
I was able to bike around to several build sites on the last day of the convergence and get a sample of some of the highlights. There are going to be some great collaboration opportunities for the 2012 CBA Conference in Portland!