Virtualizing OS

Anyone here have any virtual machines, and if so, what OS and what do you use it for? xD

Ubuntu for some light use like word processing and tinkering.

 

I use a ton of VM's because it's a good way to isolate and control the amount of memory and cpu that each VM recieves.

ESXi 5 Server running several VM's.

     1. PS3 Media Server - Centos

     2. DD-WRT x86

     3. SRCDS - Ubuntu Server

     4. Minecraft - Centos

     5. General Server (FTP, VPN, Etc) - Centos

     6. A few other internal network VM's that I care not to mention here.