My personal favorite is Virginia Barbecue Company in Ashland. Buzz and Ned's on Boulevard in Richmond was really good, but I haven't been in years and am not sure if it's still there.
I'm not much of a fan of Grandpa Eddies even though I live right down the road from it. I think their basic Q recipe is good, but their ribs and chicken haven't blown me away. They do have great wings.
And I'm glad nobody has mentioned Bill's