Meta Search Engines
"Unlike search engines, metacrawlers don't crawl the web themselves to build listings. Instead, they allow searches to be sent to several search engines all at once.
Vivisimo | Kartoo | Ithaki | WebCrawler | Dogpile | Metacrawler
To search for hard to find articles in magazines and journals going back to 1998.
Finds individual articles from many free magazines online. Also links to those magazines' web site.
Gateway to 21st Century Skills
This site "provides "one-stop, any-stop" access to the substantial, but uncataloged, collections of Internet-based educational materials."