The Y!Q service offers "contextual" search that analyzes the page being read and gives a list of related search results.
Instead of starting a search from a text box, a person would search while reading a specific page. For instance, a reader looking at a news story about the State of the Union address might highlight the phrase "Social Security" to get a listing of pages that deal with that topic.
The company, which has released the service in a test format, said it is making the coding available to Web designers to embed in their sites, so that the tool can search their pages. Yahoo is also offering versions of the tool for its news site and as a toolbar that readers can download and run on their browsers.
The battle among Yahoo, Google, Microsoft and others is extremely heated, with new services coming almost daily. Just in the past several days, Microsoft replaced Yahoo's search technology, IceRocket.com to help visitors find and download video and music, and Amazon.com began into the yellow-pages portion of its A9.com search site. At the same time, Google has continued to its service and recently released .
While Google is the definite champion right now, there have been signs that its competitors are.
As for Yahoo's new service, "it is more of an interesting new feature than a Google killer. We'll see how it goes," said Danny Sullivan, editor of SearchEngineWatch.
Sullivan said that enabling people to generate a search while they are on a Web page may resonate with some people but that the more exciting news will come if and when Yahoo decides to add advertising to the product.
If Yahoo allows Web site operators to use Y!Q to run targeted advertising on their sites, the new product could compete with Google's AdSense program, which pays Web site owners who put Google ads on their content pages and attract Internet surfers who click on the ads.
"It potentially gives them a rival to Google AdSense," Sullivan said.
Reuters contributed to this report.