Awesome project created by an undergrad at Brown!
Incredible answer to this question that really makes it clear. If I teach stats, I'm going to use whuber's example.
It turns out, Google has data on enough search terms that something is always quite highly correlated with your curve! This is a crackpot conspiracy theorists dream!
We lean from homework, not from lectures. Nobody is surprised but it's still useful to see.
Very cool statistics demonstration on OLS. Clearest demonstration I've seen.