Open thread: What visualization tutorials do you want to see?
After the county map tutorial a few months ago, I decided to write more how-to posts. Since then, with the new tutorials, it's been great seeing the excitement over visualizing your own data. So now, a question for you.
What visualization tutorials do you want to see next?
Obviously I can't teach everything since I still have plenty to learn myself, but I'll be sure to give everything a try. Leave your suggestions in the comments below.