Yahoo!’s updated Yahoo! Toolbar includes improvements for both IE and Firefox users. For users of IE 5 or 6, tabbed browsing capability has been added to appease users until IE 7 is released. The Toolbar for Firefox users has been updated in response to requests from the browser’s users, which included bookmarking, e-mail alerts, and AntiSpy.
Along with these upgrades, Yahoo! is giving users the option to directly tag their favorite content from their browser with their recently acquired bookmarking service, del.icio.us. This feature is optional and can be turned on and off.
Google, MSN, Ask.com, and AOL all have toolbars as well. Amazon also has a toolbar integrated with its A9 search engine, which also gives frequent search users a 1.57% discount on purchases they make at Amazon.com.
Sources:
http://www.webpronews.com/insiderreports/
searchinsider/wpn-49-20060327YahooBuilds
ToolsForToolbar.html
http://blog.searchenginewatch.com/blog/
060327-085225