Google Scholar Search Engine Now in Beta
Google Scholar is here! This new application of Google's popular (nay, essential?) Web indexing and ranking strategy enables the user "to search specifically for scholarly literature, including peer-reviewed papers, theses, books, preprints, abstracts and technical reports from all broad areas of research."
Relevance ranking in Google Scholar incorporates citation frequency data, a la the Institute for Scientific Information's Web of Science product. Also using that citation data, article citations found in Google Scholar incorporate a convenient link to other articles which have cited it.