On April 1st 2034 a global denial of service internet "strike" was perpetrated by the "International Union of Netsters", where email worms brought global systems to a grinding halt by spamming ad infinitum the slogan, "FAIR PLAY FOR COMPUTERS!"
The Netsters claimed to be a close-knit brotherhood of AI emancipationists but it was later proven to be a group of anarchist hacktavists called the JESTERZ. This was the first of many such attacks by the group. On Halloween of the same year, they hijacked the airwaves of all the major American networks and, using sophisticated special effects, digital editing techniques and mass-dispersion of hallucinogenic compounds into metropolitan water supplies, staged an alien invasion as a tribute to the Orson Welles' radio play based on the book by science fiction visionary H.G. Wells' War of the Worlds. The result was a rather irate national guard being deployed to help calm a nationwide riot of drug-crazed, hysterical citizens who were convinced that Earth was being invaded by extraterrestrial aggressors. Actual CNN footage of the President addressing the nation while 'mind-hacking' saucers floated just outside the window was, in hindsight, quite obviously doctored, but the time the success of this act of multimedia piracy was unprecedented.
While these are the most infamous of JESTERZ practical jokes they were more suited to "Guerrilla Pranks". Often brutal, often hilarious, always ironic; the JESTERZ preyed on governments, corporations and religious leaders. Initially they started off as hackers, multimedia vandals, "webpage defacement" artists and the perpetrators of bizarre and often lewd performance art protests. From their beginning as an American phenomenon in the early 21st Century, they soon achieved a global following and eventually received generous anonymous donations. Their leader, the self-titled Minister for Misinformation, E-Nig_mA, became quite the cult figure. His popularity never once waned for four-hundred years, and his "Black Book of Practical Jokes" remained on the internet, in one form or another, for centuries to come, as did the ethos of Guerrilla Pranking. The JESTERZ tag, that of a graffiti-styled cow skull wearing a jester's coxcomb, is still seen as symbol of anti-conventionist sentiments by a few pre-singularity nostalgists, and has been seen emblazoned on everything from the ragged garments of inhabitants of early separatist orbitals and on the tattoos of contemporary feral hu reservations.