In late 2003, Google unveiled a new index, separate from its main web index, that it queries if it fails to find good results in its main index. For unusual or obscure queries, you may see some of these results. They'll be flagged with the text "Supplemental Result" next to the URL.

Google's supplemental results have become a topic of conversation again recently, in the early days of the BigDaddy rollout. During the last few weeks of the BigDaddy rollout, large numbers of otherwise well-linked web pages were showing up as Supplemental Results. Google acknowledges that they are working to fix the problem.

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