A virtual machine monitor for x86 that supports execution of multiple guest operating systems with focus on performance and resource isolation. Describes architecture, documentation, changelog and downloads. [Open Source] http://www.cl.cam.ac.uk/Research/SRG/netos/xen/index.html
XenSource enables enterprise-grade virtualization and is the home of the open source Xen hypervisor project. Description, community, company. http://www.xensource.com/
Simulates a x86 processor and can be used to run Linux as a guest. It also can be used to accelerate bochs by executing user code inside the plex86 VM, while letting bochs execute kernel code and IO functionality inside the emulator. http://plex86.sourceforge.net/