The magic of nonpersistent drives in VMware
Who in their right mind would purposefully go and mess up a perfectly good fresh install of FireFox? I would. Franky, I am using it as an example just because I am sick of all the media hype that firefox is so much "safer" than IE. Call this a rant... maybe it is. I see a browser much like I see a gun. Browsers don't kill computers, people do. Anywho, what does this have to do with virtualization? Not much, really, unless you're talking about the magic of nonpersistent disks.
Screen shot follows:

A nonpersistent disk is a very handy tool in the world of unknowns where so many of us live. Basically, what it does is make changes to the disk between disks non-persistent. I know, never use the word you're defining in the defination. But, it is so simple a concept, I'm not going to spend the time looking for the words.
Here's how I use it: I have a virtual machine with Windows XP SP2 installed. Besides VMware tools and Windows updates, nothing else is installed. After I got it setup just like I like it (sans fluff), I shut it down and edited the VM's properties. Under the Disk's settings, I clicked the advanced button and checked "Independent" and then "Nonpersistent." Once the settings are applied, the VM is set in stone (until you change it back to a persistent disk again). Now I can install software, test stuff and if I mess up or don't like the results, just hit the reset button and start over. This is not as clean a solution as snapshots if you are trying to be scientific about testing or doing detailed development tasks, but for a quick and dirty sandbox, it's awesome.

I've gone in and fine tuned the VM after using it for a while. My main goal was to make it boot as fast as possible so that I could test things quickly. I found a nice little list of services to shut off on the web somewhere... If I can find it again, I'll post it here. I also defragged it before changing the disk to non-persistant. Every now and then, I'll make it persistent and apply Windows updates and then "re-freeze" it.
Be sure that if you do this for yourself, you turn off useless things such as automatic updates & system restore. Those will just slow things down. Oh, and feel free to just shut it down rather than waiting for a clean shutdown! The disk does not remember changes between reboots, so you can't hurt it!
Next up will be about VLANS and VMware Workstation/Server. And you thought that this stuff was cool before? Hold on to your pants.
Screen shot follows:

A nonpersistent disk is a very handy tool in the world of unknowns where so many of us live. Basically, what it does is make changes to the disk between disks non-persistent. I know, never use the word you're defining in the defination. But, it is so simple a concept, I'm not going to spend the time looking for the words.
Here's how I use it: I have a virtual machine with Windows XP SP2 installed. Besides VMware tools and Windows updates, nothing else is installed. After I got it setup just like I like it (sans fluff), I shut it down and edited the VM's properties. Under the Disk's settings, I clicked the advanced button and checked "Independent" and then "Nonpersistent." Once the settings are applied, the VM is set in stone (until you change it back to a persistent disk again). Now I can install software, test stuff and if I mess up or don't like the results, just hit the reset button and start over. This is not as clean a solution as snapshots if you are trying to be scientific about testing or doing detailed development tasks, but for a quick and dirty sandbox, it's awesome.

I've gone in and fine tuned the VM after using it for a while. My main goal was to make it boot as fast as possible so that I could test things quickly. I found a nice little list of services to shut off on the web somewhere... If I can find it again, I'll post it here. I also defragged it before changing the disk to non-persistant. Every now and then, I'll make it persistent and apply Windows updates and then "re-freeze" it.
Be sure that if you do this for yourself, you turn off useless things such as automatic updates & system restore. Those will just slow things down. Oh, and feel free to just shut it down rather than waiting for a clean shutdown! The disk does not remember changes between reboots, so you can't hurt it!
Next up will be about VLANS and VMware Workstation/Server. And you thought that this stuff was cool before? Hold on to your pants.