Some sad news to report. Jux2, the winner of the Search Engine Watch 2004 best meta search engine award, is no longer available.
Over the weekend, Aaref A. Hilaly, one of the developers of Jux2 told me that the service was originally designed to research search engine overlap (it sure was useful) and although they were thrilled and honored that many people also used it as a meta engine, the Jux2 team did not have the time, funding, and resources to keep the site running. Hilaly added that Jux2 did have conversations with other meta engines to see if they would be interested in taking over the service but no one "stepped up."
Here are two other tools you might want to check out that can help determine search engine overlap: