Accoona
This engine uses artificial intelligence to "understand" the meaning of the keywords in your query in an effort to deliver more relevant results. Drop-down menus allow you to set some search parameters, such as business type and location; run a News search for recent articles, Business search for facts and figures, or a Web search for relevant links. PubSub is also useful; it lets you "subscribe" to a particular search, after which the engine will continue to retrieve new information related to your search as it appears on blogs, in newsgroup discussions or in SEC filings, automatically refreshing your search results so they are ready (one click away from the home page) when you want them.