If you feel like coming into town (Red Line subway from Bethesda to Dupont Circle then about a 3-4 short blocks walk), The Tabard Inn is a great Greek experience, especially lunch in the back patio on a sunny day. It's a Washington institution!

Also in town (Red Line to Metro Center, switch to Blue/Orange to Eastern Market Metro Station), Cafe 8 on 8th Street SE is a Mediterranean/Turkish place, very good food. The special appeal of Cafe 8 is that for any reason, if you don't like the looks of the place or the menu or the wait, there are at least half a dozen GREAT alternatives (Chesapeake Room, Ted's Bulletin, Cava Greek restaurant, Banana Cafe Caribbean food, Starfish, Jordan's 8 sushi) within a block or two, and my favorite, Montmartre (French provincial), three blocks away on 7th. A great restaurant row, a very pretty Capitol Hill neighborhood, worth the trip into town.