Poettering: The Most Awesome, Least-Advertised Fedora 17 Feature

Remember that the users are actually running on a single OS instance. So shared libraries etc. are amortized across all users -- and I'm betting that, in a lab setting, the sysadmins would restrict users to running a single desktop if memory constraints really become problematic.

Now, if they all open 30+ tabs in Firefox... *shudder*