Did you know that Indiana Twitter users use "the n-word" more than Twitter users in Mississippi, Alabama, or Georgia? It's true, according to research by professors and students at Humboldt State University who filed through 150,000 tweets to find which regions tweets with hate speech come from. What's more is that they didn't just auto-filter; they actually read the tweets so that tweets using those words but not in a way that intended hate speech - i.e., "People should never say n-----" (censoring mine) - weren't counted. The Guardian adds: "The data has also been 'normalised', meaning that the scale accounts for the total twitter traffic in each county so that the final result is something that shows the frequency of hateful words on Twitter."
Of course, there are other variables - maybe Twitter users are more racist than non-users and it's entirely possible (and likely) that Southerners use Twitter less than, say, Northeastern folks, keeping their racism offline (these are my people; I know them).
But it's still an interesting look at where the hate speech generates.