Scirus searches an international collection of institutional repositories and other resources, so it can be a good way to find technical reports, preprints, and other less common publications.
Scirus includes basic and advanced search functions, and sorts results into journals vs. web sites. Elsevier ScienceDirect journals are prominently featured in the journal results, with direct links. USC subscribes to the majority of ScienceDirect titles, so Scirus is a good way to search those online journals. For more detailed information, see this electronic resources review in the online peer-reviewed journal <a href="http://www.istl.org/07-winter/electronic3.html">Issues in Science and Technology Libraries </a>