Ubuntu Livecd over network?

[linuxisevolution]

I now have my Debian 4 server back up, but is there anyway that I can make an iso file on the hard drive bootable to any pc on the network? My idea would be to set the first boot sequence as the hard drive on the desktops, and then network boot as the second. That way, if the hard drive fails on any of the desktops at work, they will automatically boot into the Ubuntu Live cd until I can fix the problem.

Is this possible?

My server:
550mhz Pentium3
128mb ram
8gb hdd.
nfs, ssh, and sshfs file server.


Thanks!