DeepWeb
http://www.scirus.com/
http://www.scitopia.org/scitopia/
http://www.science.gov/
http://www.scienceresearch.com/scienceresearch/
http://www.scienceaccelerator.gov/
http://www.techxtra.ac.uk/
http://search.optics.org/
http://www.hw.ac.uk/library/electresa2z.php
http://hwlibrary.wordpress.com/2008/09/22/science-search-engines/
http://www.deepwebtech.com/
http://www.incywincy.com/
http://www.deeppeep.org/
http://www.infoplease.com/index.html
http://aip.completeplanet.com/
http://www.intute.ac.uk/
http://vlib.org/
http://infomine.ucr.edu/