In competition with Google Scholar, there's Elsevier's Scirus, which calls itself "the most comprehensive science-specific search engine on the Internet". Their Advisory Board includes linguists Tony Aristar and Helen Dry, the folks who brought you the Linguist List. Scirus' list of sources is impressive but not all openly accessible: several key resources, like Elsevier's Science Direct and the American Institute of Physics' Scitation, will only be available to those with subscriptions. (The same is true of some of the content indexed by Google Scholar.)
Scirus has been around since 2001, as this 10/15/2004 article from Library Journal explains. I think it's fair to view it as an attempt by Elsevier to lessen Open Access pressures, or at least the OA pressures that are due to the desire for more sophisticated and integrated searching. Of course, it increases as well as protects the value of Elsevier's extensive inventory of scientific journals. Whatever the motives behind it, my experience is that it's an excellent search tool.
Their web site explains that the name Scirus was taken from a passage in Pausanius' The Description of Greece:
"To the Eleusinians who were warring against Erechtheus, came a man, Scirus by name, who was a seer from Dodona, and who also established at Phalerum the ancient temple of Athena Sciras. After he had fallen in the battle, the Eleusinians buried him near a winter-flowing river and the name of the region and the river is from that of the hero."
This strikes me as one of those examples where additional information weakens rather than strengthens a case. Scirus is a perfectly fine English brand name in phonetic terms, with an appropriate echo of science and citation, and a certain amount of neo-classical dignity. It doesn't improve my opinion of the service to learn that Scirus was the name of a minor religious figure who made his living by hearing the words of Zeus in the rustling of oak leaves, and who got himself killed fighting the Athenians on the side of the Eleusinians in a minor battle during the 5th century BC. Is this the spirit that I want tracking down scientific citations on my behalf? I don't think so.
Posted by Mark Liberman at December 1, 2004 08:24 PM