Share 'What virtualization software is your organization using?'

I've worked with different virtualization software in production and test environments. I wanted to start this thread to see what virtualization software others are using. If I'm not mistaken, vmware has been around the longest and is on most production servers. However, ms virtual server r2 has come a long way and looks promising in replacing workstations with thin clients. Openvz is good for v…