Scirus

Scirus: This topic-specific search engine » focuses only on Web pages containing scientific content. …is the most comprehensive science-specific search engine on the Internet. Driven by the latest search engine technology, Scirus searches over 167 million science-specific Web pages… Scirus has proved so successful at locating science-specific results on the Web that the Search Engine Watch Awards voted Scirus ‘Best Specialty Search Engine’ in 2001 and 2002.»