Google Base
Google Base is an online database provided by Google into which anyone can add almost any type of content. As of 2005, it is available to the public as a beta version, however the rest of Google's services do not yet contain information about, or link to, information from Google Base. Because information about the service was leaked before public release, it generated much interest in the IT community prior to release. Google subsequently responded on their blog with an official statement:
"You may have seen stories today reporting on a new product that we're testing, and speculating about our plans. Here's what's really going on. We are testing a new way for content owners to submit their content to Google, which we hope will complement existing methods such as our web crawl and Google Sitemaps. We think it's an exciting product, and we'll let you know when there's more news."
A major component of Google Base is acting like a classified ads service, such as Craigslist. However it has also been used for such items as protein structures, current events, real estate, recipes, and more.
Google Base Screenshot