Trapizzini - delicious little sandwiches made from goodies like artichokes, meatballs, beef tongue, involtino (cheese, guanciale, and other stuff folded into a meatball), octopus, tripe...and any number of other delicious ingredients, served in a pocket of bread with sauces that will make your eyes roll back in your head.
Next time you're in the eternal city, check it out: www.trapizzino.it.
Thanks for the tip Marco Moroder!