Yahoo! Axis redefines what it means to search and browse the Web.
Comes as a browser plugin (tested in Chrome) which adds a search bar layed over the bottom of your browser window.
As Chrome already offers searching via the address bar (FYI: In Chrome Canary it already searches as you type), the true benefit will only be gained if you use the companion iOS apps.
UPDATE: Better not to install the extension (or any extension by Yahoo! for that matter) as the extension was shipped along with the private key to sign it. Best someone just got fired at Yahoo! today. — via a comment by Duckbuster