There is a recent flurry of activity happening on the Transition Cascadia website. They are talking a lot about different definitions of bioregions, watersheds, trade zones, local currencies, etc.... you all might be interested in checking it out. Paste the URL below into your search bar:
This URL will take you to a speech by David Boyles and the unleashing of the Brixton Pound. When I read it and followed the comments at the bottom I found a link to the speech itself if you are interested.