Free registration required to read the article. “Google executives have long conceded that one of their great fears is to be overtaken by a more advanced Internet search technology. Vivisimo, a company founded by three former Carnegie Mellon University computer scientists, is hoping to prove that Google’s worries are well founded.

Four-year-old Vivisimo plans to start Clusty, a free, consumer search service based on results from Yahoo’s Overture engine, Thursday.

Vivisimo already offers a search service for corporate customers, which clusters results into categories to make them easier to sort through. Search “swift boat,” for example, and Vivisimo returns 149 results - listing them one by one, and also as a table of categories, like “Swift Boat Veterans,” “John Kerry” and “Patrol Craft Fast” on the left-hand side of the Web page.

The new Clusty service for consumers, which will be free and supported by advertising revenue, uses a similar organizational structure. But it also presents a series of tabs enabling the user to see results from sources besides the general Web, including shopping information, yellow pages, news, blogs, and images.

Vivisimo, which is privately held and is profitable, according to its executives, has been selling its clustering technology to corporations for research by their employees. Now Vivisimo is making an effort to compete more broadly by attracting consumers to its Web site, clusty.com.”