What about Dogpile? I think that they find results from different search engines.
Quote from Dogpile's homepage:
Dogpile makes searching
more of the Web easier by
returning the best results
from these leading engines:
Google Â· Yahoo Â· Ask Jeeves
About Â· LookSmart Â· Teoma
Overture Â· Teoma Â· FindWhat
Dogpile uses innovative metasearch technology to search the Internet's top search engines, including Google, Yahoo, Ask Jeeves, About, Teoma, FindWhat, LookSmart, and many more.
With one single click, Dogpile fetches the best results from the combined pool of the best search engines -- instead of results from just one single search engine.
And Dogpile makes it easy to refine your search so you can find the most meaningful results right away. No wonder it's the "Top Dog" of the search industry.