Block a website on a domain workstation with no admin rights

Is there a way to block a website even temporarily on an XP machine
when you have no admin rights? I have a group of guys that stand
around watching youtube all day instead of working. I am ex-IT and
could use a hacked bootdisk and clear the local admin password and
then change the host file, but I don't want to do that. That would
probably get me fired. I have went to management and they say we can't
block youtube since all machines would be affected and youtube is a
resource we need at times. Problem is these guys on this one PC abuse
it. I know it can be blocked based on IP address via the firewall.
Facebook is blocked so I know they have a firewall. The IT staff there
is clueless. Any ideas how to block youtube? I am to the point where I
will just disconnect the antenna on the wireless card just to keep
these guys off. They play offensive music in retail environment and my
customers get offended by the F bomb every other word. The PC is right
at the cash registers.

Any ideas?