While poking around the Hyperstition archives looking for something else, I’ve found Reza explaining an
Islamic Middle Eastern hypersigil technique (which also happens to be the inspiration for the Japanese novel and film Ringu).
Update: I haven’t found any other reference to this technique… Did Reza make this up? Anyway, could be an effective for anyone willing to mess with such a potentially damaging technique.
Update: Reza provides more info here.