According to Aleister Crowley, one of the founders of the 20th century occult underground, "Magick is the Science and Art of causing Change to occur in conformity with Will". By spelling magick with "ck", he sought to differentiate it from the secularized, pop-cultural "magic" performed as tricks in circuses and on fairs. Nevertheless, Crowley's "magick" became pop culture as well: in 1960s underground movies to 1980s industrial music, to name only a few. Does computer and hacker culture mark the ultimate point of convergence of "magic" and "magick"? What is the occult underground in computing? And how does relate to contemporary art and design experimentations with the medium? This talk will attempt to trace "magic" and "magick" from Sgt. Pepper's Lonely Hearts Club Band via disk defragmenting software to contemporary memes and the Anonymous movement.