John (aka "Meatloaf") used to run a program on his board that interacted with a user as if they were chatting with the SysOp. He posted a log of such a conversation once and it was a riot. Ended with something like:
"John: Press Alt-H to increase your access." "User: Okay." "User: @#$JKUADUaasdfUIWERU!#@&*(" "User: NO CARRIER"