Allagash

The 18th most popular microbrewery in the U.S.:

Allagash Brewing Company: Allagash started out brewing a Belgian Wit beer, Allagash White, and has expanded to a variety of bottle conditioned beers. This involves a second fermentation in the bottles after the initial fermenting in tanks. It adds an air of complexity to the beers, and the novelty of drinking a "living" beer, via Travelhacker