Uncle Sam's gets the award for best cheese steak in the Burgh. This was a frequent lunch stop for me when I worked in the area. As I recall they only take cash so, if you only have a card on you, rob a bank or something because you do not want to miss out on this. Cheese steaks are top-notch but if you get there earlier in the day try the provolone and egg sub as a special breakfast treat. Then go back for lunch.... and dinner.
Tip: You must add sweet potato fries to your order - I think this is actually a law in all 50 states.