Roli Roti is a food stand by the Ferry Building and the location does move, so just look for the line.  The secret is to get there when they first open, and then there is no line and it’s easier to find a seat somewhere in the area to enjoy your sandwich.  They are only open on Thursday (10 am – 2 pm)  and Saturday (8 am – 2 pm) but their signs encourage you to hire them to cater your next party.  They have the rotisserie going as you walk up and you can see the chickens and pork rotating slowing dripping their fat and juices on the potatoes below.  I have been many times and it’s a great snack – the smell is wonderful – but I’ve only tried their porchetta sandwich.  They cut the meat while you watch and load it onto a wonderful soft, chewy roll and then cover it with onion relish and arugula greens.  There are bits of the crackling crust of pork intermixed with the tender, juicy pieces of pork.  I will admit that some days have yielded a better tasting meat than others but it always is rich, decadent snack or meal.  Try it if you’re there at the right time and then on Saturday you can walk through the wonderful farmer’s market behind the building or cruise through the fun shops in the building.