This is a fascinating study of dialectic trends in different parts of the country. There are 122 questions about things like how do you say "coupon", or "what do you call the little grey creature that rolls into a ball when you touch it", and lots of other interesting stuff. Then they coordinate the answers by region of the US, and show you a picture of the results.

What's really interesting here is that a lot of trends that I would expect to be localized are actually pretty well distributed throughout the country. What I really wish is that I could look at data for these questions every ten years, for the last hundred. Back before instant communication, and before we all used to move often and travel widely, these things would have been in isolated pockets, and the country would look like blotches. There are still area-wide trends, but you can really see the scatter effect of media and travel.

http://hcs.harvard.edu/~golder/dialect/maps.php