Who's Using Open Source?

Amazon.com
DaimlerChrysler
DreamWorks - animators use Linux desktops and movies are rendered on Linux servers
Flickr, an immensely popular online photo-sharing Web site, operates exclusively on open source software
Ford Motor Company - Linux chosen without Microsoft® getting any serious consideration
Google - the leading internet search engine is powered by [Linux] and Python. "Google Inc open source programs manager Chris DiBona pointed out that if Google used Windows, or any other non-open source software program, to make changes to that system he would be required to essentially ask permission from that vendor. 'Why should we hand over the control of our software support to another company?'" (Ascierto, Rhonda. "Unhappiness drives open source adoption" Computer Business Review Online 10 Aug 2005)
IBM
Indian President A.P.J. Abdul Kalam has called for broader adoption of open source in India and believes it's unfortunate that his country relies on proprietary software (May 2003, ZDNet)
Indiana Department of Education - schools in the state have added Linux workstations for 22,000 students under the Affordable Classroom Computers for Every Secondary Student (ACCESS) program
Industrial Light & Magic - Since 1996, "Python's unique mix of simplicity and power continues to be the best available choice for controlling ILM's complex and changing computing environment." (Industrial Light & Magic Runs on Python - Tim Fortenberry, Jan 17, 2003)
Los Alamos National Laboratory - among other Linux systems, a cluster called Lightning containing 2,816 processors on 1,408 nodes
Merrill Lynch
Morgan Stanley
Munich, Germany - 14,000 PCs migrating from Windows to Linux and replacing Microsoft Office with OpenOffice
NASA - uses Linux to make custom software programs for research and development
Oracle - All software is programmed on Linux
RealNetworks
Schools in Extremadura, Spain - 80,000 computers loaded with GNOME, Linux and other open source software. The total cost savings exceeded 18 million euros (Gnome.org)
US Department of Defense - the first federal agency to sanction the use of open source and Linux
US Department of Energy - uses Linux to make custom software programs for research and development
US National Security Agency - developed and released a security enhanced version of Linux used in the public and private sector, even weapons systems used in Iraq
US Postal Service - Linux-based systems in 250 mail distribution centers in its mail routing processes
TiVo, Inc. - 640,000 personal television recorders and back-end servers
Verisign, Inc - 1,100 Linux servers
"Petrochemical giant BP has purchased a large cluster of Hewlett-Packard Linux servers using Intel's Itanium 2 processors to help search for oil and gas deposits. BP bought 259 HP rx5670 systems, each with four Itanium 2 processors. The systems collectively have more than 8,000GB of memory and can perform 4 trillion calculations per second." - April 22, 2003, CNet News.com
The Supercomputing Education and Research Centre of the Indian Institute of Science has commissioned what is arguably the most powerful single-platform Linux computing facility in the country: an Altix 3000 system from Silicon Graphics Systems India (SGI).
Verizon
Yahoo!