Happen to be talking with an MSWindows admin about disaster recovery. He was talking about how it was a challenge to do recovery. I made a bet that I could have network of computers running in no time and not even use a single hard drive. I would need one cdrom though. Of course I was told it could not be done. You can guess what happened next with the wallets.
Anyway, we went around and made sure that all the machines would pxeboot except the system with the cdrom drive. I booted a Knoppix linux cdrom which has a built in terminal server. Once the machine was up, I made a few quick settings for the terminal server. We started booting all the machines. low and behold after a bit all the other machines were up and you could use all the software.
To make a long story short, the admin was dumbfounded and became an instant new devotee of linux.
See how you can at: http://www.instructables.com/id/No-hard-drive-network/ or http://www.instructables.com/id/Another-almost-free-computers-thin-client-set-up/ .
To convert a Rasperry Pi to an LTSP thin client see: http://www.instructables.com/id/Raspberry-Pi-Jack-of-all-trades/#step7