Back in the 70's when I was in college (WPI), our computer center used a bunch of HZ2000s at the center itself. (our system at the time was a KA based PDP-10). An oddity of the TOPS10 monitor (or at least the version that we were running) was that it let people send messages between terminals even if no one was logged in. One of my friends figured out that if you opened an unassigned terminal in the computer center (usually after hours)from a remote campus site, you could dump a series of commands (usually including "send" commands :-) to the HZ2000, terminated with a "send screen" command sequence. This let you send messages that looked as if they originated from the center to another remote terminal.(Heck, we were just college kids, and it was an innocuous bug. Boy, I miss those days :-). -al-