330. Wot, No Coffee?

At Cambridge University, a coffee dispenser used to be kept in a corridor just beside the Trojan Room and people from all over the building used to come and consume coffee at that point. The Trojan room housed the notorious Computer Science Hackers who used to guzzle coffee like there's no tomorrow and so most of the time the other people had to return back disappointed from the dispensing machine after having walked an exhausting floor or two. To put the other guys out of their discomfort, what innovation/first did the Trojan Room inmates come up with in 1991, thereby giving rise to a widespread internet phenomenon today??