American Institute of Chemical Engineers
Serving Chemical Engineers. The AIChE Web is geared towards advancing the practice and theory of Chemical Engineering.
http://www.aiche.org/

Science-Network
Recruitment services and job information for scientific and medical professionals.
http://www.science-network.com/

Science Jobs
Free site for job seekers listing industry, academic, and government bioscience employment opportunities.
http://www.sciencejobs.com/

ScienceCareers.org
ScienceCareers.org is dedicated in matching qualified scientists with jobs in industry, academia and government. ScienceCareers.org and its editorial voice, Science’s Next Wave, work together to offer the best scientific information out there.
http://sciencecareers.sciencemag.org/