In the near future, I'll be coming to Philadelphia for several days. I'll be going out for dinner a couple of times with groups of out of town friends, and I get to pick the restaurants. I am looking for interesting--flavorful, adventurous, etc.--food at a fun place to eat, within a 5 to 10 minute ride of the Marriott on Market St., preferably under, say, $40 a person. I don't know the city at all. What shouldn't we miss?