You can find information & resources of science, biotechnology, chemistry, ecology, technology, science resources, mechanical engineering, earth sciences, astrophysics, nuclear & molecular at PortalScience.com
Astro Place
astronomy educational and informational links.
http://astroplace.com/
Astronomy News & Links
follows current astronomical research and makes links available to recent announcements and press releases of new observations.
http://www.astrophys.org/
astronomylinks.com
source for astronomy and space related links from around the world.
http://astronomylinks.com/
FinderScope.com
guide to resources for learning more about stargazing, amateur astronomy, celestial objects, and observing equipment and techniques.
http://www.finderscope.com/
Galactic Surf
selected links with editorial commentary to sites about astrophysics, exobiology, particle physics, exoplanets, space missions, cosmology, deep space galleries, and more.
http://www.galacticsurf.com/