Science.gov searches more than 55 databases and 2100 selected websites from multiple federal agencies, including DOE, EPA, NASA, NIH, NSF, USDA, and USGS. It is an excellent resource for finding a wide variety of documents related to government conducted or funded scientific research. An interagency initiative first released in 2002, Science.gov 5.0 now offers features such as image searching, email or RSS search alerts, and clusters to help users refine searches.
Science.gov is currently conducting a user survey to gather feedback on the interface and results sets.
If you would like help using Science.gov or setting up alerts, contact your librarian!