This is from the ECMWF which has pioneered the use of Supercomputers starting with the Cray (and regular replacements of phenomenal computing power) since the seventies for their weather predictions. This extract just deals with the user's dektops and although they are primarily running Linux, allowing a guest OS to run under it such as Windows for where Linux cannot run those particular programs.
This must rain on Bill Gates's parade for Windows to be controlled by Linux.
ECMWF wrote: Introduction
All users within the Centre are provided with an IBM PC which runs Linux. The PCs are currently running the SuSE 9.1 distribution.
The Linux systems provide most facilities that users require - such as web browsing, email access, file editing and terminal access to other systems. In addition, Metview and other visualization facilities are available.
Access to some Windows software applications is also required, in particular Microsoft Office and Macromedia Dreamweaver. This is achieved using VMware Workstation from VMware Corporation (http://www.vmware.com" onclick="window.open(this.href);return false;), which allows a second guest operating system to be installed and used under Linux. In the Centre's case, the guest system used is Microsoft Windows. Access to the Unix HOME filesystems is provided by using Samba.
Under VMware, the PCs are currently running Windows XP with Microsoft Office 2003.
The PCs installed are either IBM Intellistations or Lenovo M52s. The IBM Intellistations have 2.0 to 3.4 GHz Pentium 4 CPUs, 1 GB memory and Nvidia Quadro2 or Quadro4 graphics. The Lenovo PCs have 3.4 GHz CPUs, 1 GB memory and built-in Intel Xtreme Graphics.