A surprisingly well done NY Times dialect quiz:
Most of the questions used in this quiz are based on those in the Harvard Dialect Survey, a linguistics project begun in 2002 by Bert Vaux and Scott Golder. The original questions and results for that survey can be found on Dr. Vaux’s current website.
The data for the quiz and maps shown here come from over 350,000 survey responses collected from August to October 2013 by Josh Katz, a graphics editor for the New York Times who developed this quiz. The colors on the large heat map correspond to the probability that a randomly selected person in that location would respond to a randomly selected survey question the same way that you did. The three smaller maps show which answer most contributed to those cities being named the most (or least) similar to you.
Pretty much everybody who’s tried it (and is from the U.S.) is struck by how accurate it is; I expected to bamboozle it, since I’m from nowhere in particular, but it pegged me as from the Los Angeles area, and since that’s where my father’s side of the family (originally from the Ozarks) moved to before I was born and thus where I spent a lot of time on home leave as a kid, as well as where I went to college, it’s probably the biggest single formative element in my way of speaking. Thanks to Bill, Paul, and anyone else who may have sent me the link!