Case 1:
You’ve an advanced web developer or administrator and you’re on the road traveling. You arrived at your hotel, check in, and get to your room to crash. Then you remember that *thingamajig* on the server you need to tweak/update, so you fire up your laptop and hop on the wifi network, launch the VPN client, only to find it’s not working. Close inspection reveals that the local network range of hotel’s wired and wifi networks replicate the range used in the network inside your remote VPN. Hmmm…

Well, since you have a development VM running behind a virtual NIC with a different IP range, you log in to that and proceed to connect over VPN and slap the *thingamajig*. Voila, IP conflict bypassed virtually, and you’re back to resetting *thingamajigies*.

Case 2:
You’re a web developer, but you don’t want to make mush of your laptop by installing every latest client *widgimadijit* on your nearly pristine OS, because it would make your computer fugly and slow, all those *widgimadijits* don’t work together anyway, and it would put your MP3 collection at risk. So, you waltz on over to virtualappliances.net/products/ and choose right VM for your project, load it up, customize it, and leave your foundation OS clean and sleek!

When you wrap up phases of your project, you sync the db and web content from your VM into staging or production. No fuss, less muss.

Case 3:
You have legacy (”old”) software you don’t want to (or can’t) repurchase, so you run a copy within the appropriate OS as a VM. (Note to Apple, when will OS X have that feature?)