From the website: "If you've checked out any of the sites for Firefly and/or Serenity fandom, you already know that the Browncoats are a proud bunch of folks. We've done the impossible, and that makes us mighty, and all that. Although our show was cancelled and our movie wasn't a blockbuster, we're still Browncoats and we will continue to show our support for the Firefly universe for many years to come.
One of the best ways I can think of to do this is simply this: wear it for everybody to see. :) Wear fashions that work for your own personal style that are based on those in the Firefly universe. Wear your Browncoat patches, tshirts, caps, bracelets, what have you. Simply wear the color brown, if nothing else - wouldn't it be a proud day when big name fashion designers notice a trend toward brown-colored clothing, because we've been buying it all up for our own use?"