I like taking friends to the District Chophouse and Brewery (
www.chophouse.com ) in Chinatown, though their food is better than their beer.
By the same owners as the Brickskeller is RFD, also in Chinatown (
http://www.lovethebeer.com/rfd.html ), which has 30 beers on tap and a couple hundred bottles as well. Service and food range from mediocre to atrocious, but then, it's a sports bar now, and a better atmosphere than the Big Hunt.
By the way, although there are many bars around named the Brickskellar, the one in DC is the BrickskellER. And while they claim to have 800 beers available, in reality they'll be "just out" of at least ½ your requests. It's still impressive, but by the third time the waitress comes back empty handed it's also quite irritating.