Ask Jeeves

Allows user to submit questions in plain English
 

Google

Ranks pages by number of links from other highly-ranked pages

HotBot

Places results into clusters, eliminating multiple hits to the same site

IxQuick

Claims to be the world's most powerful metasearch engine

Search results include "Are you looking for:" which helps with misspellings and also helps narrow search

Northern Light

Results organized into customized folders to help user narrow search

ProFusion

Categorizes queries and selects best sources based on past performance

Vivisimo
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