Lovely SPAM, wonderful SPAM

Monty Python - SPAM

In the 1980s the term was adopted to describe certain abusive users who frequented BBSs and MUDs, who would repeat "SPAM" a huge number of times to scroll other users' text off the screen. In early Chat rooms services like PeopleLink and the early days of AOL, they actually flooded the screen with quotes from the Monty Python Spam sketch. This was used as a tactic by insiders of a group that wanted to drive newcomers out of the room so the usual conversation could continue. It was also used to prevent members of rival groups from chatting -- for instance, Star Wars fans often invaded Star Trek chat rooms, filling the space with blocks of text until the Star Trek fans left. This act, previously called flooding or trashing, came to be known as spamming. The term was soon applied to a large amount of text broadcasted by many users.
Spam (electronic) #History, Wikipedia.