I have a confession. I'm addicted to Virtual Machines.
It started with the free Microsoft Virtual PC. Then, like an addict, it just wasn't enough after a while. I needed a bigger fix. Then I met VMWare Workstation. Man, I am hooked!
I love using Virtual Machines especially with Teamcenter for development and testing. They are so helpful. I should have been using them for the past several years, but I only got into them seriously in the past year.
My favorite use of VM is using snapshots to do before and after backups while debugging and reproducing the problems I find before I submit an IR to GTAC. Another favorite is to use them for testing/revising my client install scripts. I'm finding new uses all the time.