It's been around for over a year now, but you may not have ever tried it out. Why should you? Because it presents your results in a graphically relevant way. Not all students (or teachers) find it easy to scan down a page to choose which link to follow. While this is still text, it's organize in a mind map type of format ... and clicking on one of the subcategories will expand out with another wheel... an so on.
For illustrated directions: http://www.googlewonderwheel.com/google-wonder-wheel-step-by-step