PhysicsWeb  - physics news, jobs and resources.
PhysNet - Worldwide Physics Department and Documents Network.
Physics section on Yahoo

Search for Scientific Information:

AAAS - American Association for Advancement of Science.
EurekAlert! - scientific news.
Euroscience

Physical Societes and Organizations:

Russian Acsdemy of Sciences
European Physical Society
American Physical Society  
Institute of Electrical and Electronics Engineers - IEEE
Institution of Electrical Engineers - IEE
International Union of Radio Science - URSI
Geoscience and Remote Sensing Society - GRSS
The International Society for Optical Engineering - SPIE

On-line Scientific Journals and Publications:

American Physical Society Research Journals
Institute of Physics Journals
Institute of Physics Online Services
Online Journal Publishing service of AIP
AIP Physics News - searchable archive of the American Institute of Physics weekly bulletin.
DOAJ - directory of Open Access Journals
arXiv.org - e-Print archive
ru.arXiv.org  e-Print archive mirror in ITEP (Moscow)
IEEE/IEE Electronic Library (IEL)
ADS Physics and Geophysics Abstract Service - searchable database of abstracts provided by NASA's Science and Technical Information Group.
Caltech Library System
SPIEWEB
Technical (Optics and Photonics) Library of the Photonics Research Center
Scientific-Technical Library
Mathematical Physics Electronic Lournal
The Astronomical Journal
Living Reviews in Relativity, Living Reviews in Solar Physics
Nature
Science
Scientific American
Journal of Radio Electronics

Grants and Foundations:

Russian Foundation for Basic Research