I'd recommend 12 Bones http://www.12bones.com/menu.html
It's in the arts district and very casual - anything from tanks and shorts to 3 piece suits. If you don't like picnic tables - this is not for you. Don't worry if you see a line, as you order at the counter and they bring your food to you. The staff and customers are friendly.
They have a good selection of sodas, local beers, and sauces. The brisket sandwich with 2 sides makes a very good sized lunch. Greens and Slaw are really good sides. I make Mac and Cheese as a main dish as my Grandmother and Mom did, so I didn't care for theirs. They close at 4:00 or when they sell out.