Google announced today that it has been working on a faster search engine that will improve results for web developers and power searchers.
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For now though, developers are being asked to go and check out the http://www2.sandbox.google.com/ and try a few searches with it. Then, compare those results with those found on the current Google site.
If a "Dissatisfied? Help us improve." link displays, click on it and type your feedback in the text box along with the word caffeine.
Since it's still a work in progress, Google engineers will be monitoring all feedback.