Every Saturday through August, Stifel & Capra (260 W Broad St, Falls Church 22046) is holding an outdoor arts and vintage market in their parking lot. It's like an addition to what they have inside -- which is a great selection of vintage goods, jewelry (artisan and vintage) and affordable art.
I didn't hear of this gallery/shop until we moved to Falls Church last year, which is a shame. I've found some wonderful vintage jewelry, kids' decor items (like this switchplate cover ($7) we put in our son's room) and wacky things like a 1950s BBQ set in perfect condition ($18). They also have a large selection of pretty vintage linens, including tablecloths. You should definitely check them out.