- Advanced Research Projects Agency (ARPA)
- Central Intelligence Agency (CIA)
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- Department of Education
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- Environmental Protection Agency
- FedWorld Information Network
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- National Institute of Standards and Technology (NIST) sites
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- National Science Foundation (NSF) sites
- National Security Agency (NSA)
- Navy, US
- Universities Space Research Association (USRA)
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Department of Defense (DOD)
- APR's Fortran parallelization tools
- Army Research Lab
- Defense Technical Information Center (DTIC)
- Standard Systems Group, Gunter AFB, AL, home of the USAF's software development center
Department of Energy (DOE)
- Ames Laboratory
- Argonne National Laboratory
- Argonne National Laboratory Mathematics and Computer Science Division
- Fermi National Accelerator Laboratory
- Lawrence Berkeley Laboratory
- Lawrence Livermore National Laboratory
- Los Alamos National Laboratory
- Los Alamos National Laboratory: Advanced Computing Laboratory
- Massively Parallel Computing Research Laboratory (MPCRL)
- National Energy Research Supercomputer Center
- Oak Ridge National Laboratory
- Oak Ridge National Laboratory: Center for Computational Sciences
- Pacific Northwest Laboratory
- Sandia National Laboratories
- Stanford Linear Accelerator Center (SLAC)
- Supercomputer Computations Research Institute
- Superconducting Super Collider Laboratory
National Institute of Standards and Technology (NIST)
- High Performance Systems and Services Division
- Mathematical and Computational Sciences Division
- Development and Dissemination of Scientific Software for High Performance Computing Systems project
National Aeronautics and Space Administration (NASA)
- Hubble Space Telescope News
- NASA/GSFC Space Data and Computing Division
- NASA HPCC Office (includes list of all NASA labs)
- NASA Information Infrastructure Technology and Applications (IITA)
- NASA Information Locator Service
- Numerical Aerodynamic Simulation (NAS) Program
National Institutes of Health (NIH)
National Oceanic and Atmospheric Administration (NOAA)
National Science Foundation
- Cornell Theory Center (CTC)
- National Center for Atmospheric Research (NCAR)
- National Center for Supercomputing Applications (NCSA)
- Pittsburgh Supercomputing Center (PSC)
- San Diego Supercomputer Center (SDSC)
National Security Agency
Universities Space Research Association (USRA)
- Center of Excellence in Space Data and Information Sciences (CESDIS)
- Institute for Computer Applications in Science and Engineering (ICASE)
- Research Institute for Advanced Computer Science (RIACS)