Thrillist does a great job with these food lists. In the past, I've found out where to get the spiciest dishes in New York, or where to go apple pickin' in New Jersey, or the best diners, or the best pizza. You name it.
So this is an interesting ranking: the 101 Dishes that changed America. It starts with the hot dog from Nathan's in Coney Island and continues through the Reuben and the Slider and Buffalo Wings ... all the way to the Rainbow Bagel. These aren't strictly American dishes. Nachos, tacos, burritos -- they're all on here as well.
Do not read on an empty stomach.