Today when I went to Google suddenly a new link appeared after the news tab - scholar. This service is still in beta and provides a search on scholarly material.

Features of Google scholar

Search diverse sources from one convenient place.
Find papers, abstracts and citations.
Locate the complete paper through your library or on the web.
Learn about key papers in any area of research.

This is the results I got for relativity. Pretty impressive.

As per Google, articles are ranked based on the text of the article, author, publication in which it appeared and how many times it is featured in scholarly material.

Google provides scholar integration services to publishers and librarians. Librarians can add their resources to Google scholar and hence Google scholar can in future become the ultimate catalog of all the libraries!

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