SCIRUS

Internet search engine for locating resources in both web pages and electronic journals. Unlike other search engines, only retrieves information and scientific content can be searched by author affiliation. Tracking over 300 million scientific web pages.
Scirus is the most comprehensive science-specific search engine on the Internet. Driven by the latest search engine technology, Scirus searches over 545 million science-specific Web pages, enabling you to quickly:
Pinpoint scientific, scholarly, technical and medical data on the Web.
Find the latest reports, peer-reviewed articles, patents, pre prints and journals that other search engines miss.
Offer unique funcionalities designed by and for scientists and researchers.

The webpage direction is: http://www.scirus.com/