I have to recommend this store (at 323 7th Street SE)to hotsauce enthusiasts. It is near Eastern market, and Brennan (Uncle Brutha) has won 20 awards for his 2 hot sauces. They aren't that hot, but are really tasty. The green sauce has ginger and garlic. The store has a hot sauce tasting bar.
I did write an article about the place for dcfud.com.