Being a sandwich connoisseur myself the LA thread inspired me...
Some of my favorites:
-Tummy Stuffer in Costa Mesa (17th st location)
-Gallos in Corona Del Mar
-Frank's Philadelphia (Costa Mesa)
-The club sandwich from Bristol Farms in Newport Beach
-Any bahn mi from the westminster area
-Italian Beef from Portillos
So many to choose from...what say you Chowhounders?