DC: Gluten free beer?
I have heard that Brasserie Beck and Pete's New Haven Pizza have gluten free beer, but I would definitely call ahead and ask.
In terms of gluten-free menus, I know that Firefly has a gluten-free menu. And I just noticed when doing some research on a topic completely different that The Melting Pot has a whole gluten free menu (which can be viewed on their website).
1101 K Street, NW, Washington, DC 20005
Melting Pot Restaurant
1110 N. Glebe Rd, Arlington, VA 22201