Somehow feeling guilty this has not surfaced on infosthetics before, but here it is anyway. Google recently introduced its so-called Wonder Wheel [google.com] as an addition to its normal results page. Next to the somewhat strange naming choice (is it a mixture of a popular television quiz show and a fabric softener?), this new feature shows how Google might be slowly stepping into the search visualization space. You should be able to see the graph for yourself, either by following the link above, or by choosing the "Show Options..." link immediately under the search box on a results page. If not, check out the movie below.
The Flash-based interactive visualization starts with the main keyword in the center, and places related terms around it in a circular fashion. Clicking on a related term creates a new, connected circle with more related terms. Whenever one clicks on a term, to the very right, the web results change to reflect your current topic of focus.
What do you think? Useful?