BASE is one of the world's most voluminous search engines especially for academic open access web resources. Key Features: Allows you to search intellectually selected resources and their bibliographic data, including those from the so-called ‘deep web’, which are ignored by commercial search engines. There are several options for sorting the results list and you can browse by Dewey Decimal Classification and document type.
Also known as the ODP or DMOZ, this site is the premier open subject index on the net. The Open Directory Project claims to be ".the largest human-edited directory on the web." Major search engines like Google, Teoma, HotBot, and Lycos, contract with the Open Directory Project to provide directory services.