Dear Friends, I just happened to hit on a search engine called - GoPubMed < http://www.gopubmed.org/ > It is an Ontology-based literature search tool. It takes the query and submits it to PubMed. The references retrieved are then categorized using "Gene Ontology terms". Which is a hierarchical vocabulary for molecular biology covering cellular components, biological processes and molecular functions. Just wondering how fast new information retrieval innovations are taking around us while we keep on dreaming to retail our conventional tools. --Sukhdev Singh, NIC. http://openmed.nic.in