[K12OSN] Making a message pop up on a thin client

[Carl Keil <carl snarlnet com>]

Hey Folks,

I've always wondered about sneaky thin client tricks.  It seems like 
there's got to be a way to blast some audio or pop up a message on a 
thin client remotely, like from the command line.  Does anybody know how 
to do that?

Thanks,

ck