MESUR: science maps and rankings from large-scale usage data
The MESUR project studies science from large-scale usage data collected from some of the world's most signficant publishers, aggregators and university consortia.
Maps of science
Explore interactive maps of science generated from large-scale usage data, including impact rankings provided for journals in the map (requires Java).
Interactive journal ranking service
An interactive journal ranking service to explore the top journals in a domain according to a variety of different impact metrics.
MESUR's analysis of more than 39 impact metrics accepted for publication in PLoS ONE (see preprint: http://arxiv.org/abs/0902.2183)