The admirably obsessed J. Slab over at Porkchop Express has compiled a quick reference guide entitled Bánh Mì-bonics which tells you everything you need to know about ordering the Vietnamese sandwiches known as Bánh Mì. This is just awesome.
My boring just-the-facts-ma'am Bánh Mì description: it's got thinly sliced, pickled carrots, daikon, onions, cilantro, and your choice of barbecued pork, paté, or chicken.
Porkchop Express's gotta-get-it-now description: "You probably don’t want this, it has three types of pork each more delicious than the last. ... I’d let you try some, but it’ll party in your mouth, and I know you already partied too hard at breakfast with Farmer Jones and that Jimmy Dean kid.”
Once armed with your pocket guide, peruse Porkchop Express's numerous reviews of pretty much every bánh mì shop in the five boroughs.