This was just too good to not save here. I stole it from www.jsiinc.com as Jerry is king of this sort of stuff it's tip 1736 on his reghack site.
I have a business full of desktop systems, users could not change the time on their systems due to a permissions problem.
Install the resource kit
run this bat file from c:\ with the command "chgtimer.bat c:\results.log" as admin from either the server or your workstation when you are logged in as admin (must be the machine with the reskit installed).
it's awesome.