Amazon is stepping up its work on A9.com, its state of the art search engine which it hopes to use to topple the mighty Google. Good luck, that's all I have to say - Google is a beast. A monolith. But they have some good and nifty features in there that might just help them to compete with Google: A9 lets people navigate, annotate and store Web pages they've visited, and as the TiVo digital video recorder does with television programs, it will recommend sites based on users' past preferences. A9 also organizes query results into expandable columns. A9's branded toolbar also records users' Web-browsing history and makes it accessible and searchable. Some great ideas, but the competition is stiff. Even if we forget about Google altogether - an almost impossible task - Amazon still have to contend with the likes of Yahoo, Microsoft's MSN and Ask Jeeves, who all have their eye on the position of top dog search engine.