Yahoo! has extended its toolbar browser plugin to confront one of the leading menaces on the Web: adware. Yahoo!'s updated Anti-Spy software provides users with detailed information on identified categories of spyware that may be found on their computers, the option to review potentially harmful software prior to removal, and as a new addition, adware detection.

Yahoo! Anti-Spy has been available since May, but since then updated features have only been available to a limited beta test audience. A wider public release is expected sometime this week, and the service will continue to be free of cost. Yahoo! Toolbar is the only toolbar that offers these privacy enhancing capabilities.

Other leading toolbar products offered by Yahoo!'s chief rivals MSN and Google have yet to incorporate detection for either spyware or adware. Toolbars are the latest channel used to draw traffic into search sites and are designed to build brand loyalty by including value added features that are often distinct from the competition.

For instance, Microsoft has also announced a prototype toolbar that is capable of searching beyond the Web and onto the desktop. Rival Google is also developing a similar technology that searches for files and text code-named "Puffin", while Hot Bot has already made HotBot Desktop available for download.

Aside from its abilities to tackle malware, the Yahoo! toolbar has one more distinct feature. The software is powered by Yahoo!'s own algorithmic search engine that supplanted one licensed from Google.

Yahoo's new search engine is built on top of technology acquired from Inktomi, and its launch marked an unofficial end to its partnership with Google dating back to October 2002. Since that time Google has worked feverishly to distinguish itself from other search engines by including new features such as the ability to browse by name.

Yahoo! was not alone in its decision to develop a homegrown search engine. Microsoft's MSN business unit is currently developing its own with an emphasis on returning search results that are more relevant than its competitors.

In addition, MSN is developing two specialized search engines that scour through blogs and over 4,800 worldwide news sources to produce search results.