Game Parlor has two locations, 1 in Chantilly and 1 in Woodbridge. Great selection of minitures including D&D,Reaper,Warmachine/Hordes,GamesWorkshop(40k and fantasy), flames of war and many others. They have a huge selection of role-playing games (including D&D, Paranoia, whitewolf, and Shadowrun), as well as a good stock of strategy board games (axis and allies for example), and family style games like settlers of cattan, ticket to ride, and more.
Staff is always helpful, and if you are looking to pick up a newly released game I'd strongy encourage you to pre-order through them. I've used this service and it is a great way to get something at the time of release (at no extra charge).
I would note that they don't carry video games, but they do have PCs you can rent to play some multiplayer computer games.
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