Exposing The Deep Web

Defined:

"The deep web (or invisible web or hidden web) refers to World Wide Web content not part of the surface web indexed by search engines. Less commonly, the term deep web may represent deeper interaction."

The argument could be made that Technorati is a deep web search of sorts in the blog world and that could extend out to things like Eurekster the notion of social search as well.

From what I can gather, all the search engines that attempted to do this have failed. Anyone know of any still running? Would be fun to see the difference between a deep web search and a traditional google search.