Any chance of making it click-based? For example, once I open it, I'd rather click on Markets than hover to change the right side.

Also, and I realize this was just for fun, making it responsive would be a nice touch. For example, force the right col under col 1 and col 2 below a certain width. That's easy and I think more people are likely to find the example more useful.

Otherwise, sweet! Good stuff. Thanks for sharing.