Amazon's new search engine has some nice features. For instance, they keep an indexed history of all my searches. Google also keeps this data, Amazon makes it available to me instead of simply using it for their own purposes. In addition:

] A Diary so you can take notes on any web page, and
] reference them whenever you visit that page, on any
] computer that you use.
]
] Easy to use Bookmarks (Favorites), which are stored on
] our servers so you can access them from any computer.

A9.com - Company - Why use A9.com?