New Tool From Google Retailers and publishers have fought hard to work their way up in the ranking of Google’s search results and refine the search features of their own Web sites to help users once they arrive. Now, Google is taking a greater role in helping users search within particular sites. And some of the same retailers and publishers are not happy about it. The results of the search are almost all individual company pages. Google tops those results with a link to the home page of the Web site in question, adds another search box, and offers users the chance to let Google search for certain things within that site. Analysts generally praise the feature as helping users save steps, but for Web publishers and retailers, there are trade-offs. While the service could help increase traffic, some users could be siphoned away as Google uses the prominence of the brands to sell ads, typically to competing companies. For More Details Visit:
My dear friend This is not a toolbar its search inside search, This is called "Teleporting". Every site which fulfils google standard generally high pagerank website gets this search box. Don't worry this is discussed many times here. This will search your whole website before going inside from google. Generally it appears by typing domain name only but for some website it appears for generic keywords also. Short form of this search box is ( type this in google query bar "keyword:domain.com" remove inverted commas) Cool Mate and Enjoy your Day