Google released Google Base data API, which permits you to write applications on the basis of dynamic interaction with Google Base. It enables you to insert, edit , delete items , enriching the existing information. You can also query the content of other published users. The items of the content can be accessed via the API. This accredits you to create domain -specific search applications or mash-ups, incorporating Google Base content with other services. Visit Google Code blog for detailed information regarding its functionality and use.