A Bleg: Intel on DC/Northern Virginia area wine shops

Here's a "bleg" (blog beg) to any readers either living in the DC/Northern Virginia area or otherwise familiar with the wine shops there:

What are your views on the best wine shops around? Keep in mind that my preferences are for stores with a broad selection from offbeat or otherwise underappreciated regions and grapes.  I really don't care who's got the best selection of first growth Bordeaux, DRC, or cult cabs.  I'm familiar with Arrowine in Arlington, which I think is exactly the kind of shop I love.  Please include comments about why you like any shops you mention.

Thanks!