Came back from Charleston recently. Can concur on the NYT article on Hominy Grill, which luckily we visited before the article came out. It was just around the corner from where we were staying, and was recommended by some locals we met. Best soft-shell crab po-boy I've ever had.
Recommend the farmers' market, too. Small, some nice stuff, we got some excellent strawberries, and a surprisingly good knish, pronounced by one of the customers in line like "nish".