A closer look
IBM spent seven agonizing years over-engineering the Selectric typewriter's iconic 'golf ball' print head, and Soviet spies immediately weaponized it. The KGB realized that the mechanical movements of the typeball created distinct acoustic signatures for every single letter. They managed to covertly implant microscopic, unpowered acoustic bugs inside the typewriters at the US Embassy in Moscow. These brilliant mechanical keyloggers tracked the tiny physical shifts of the metal ball, intercepting highly classified American documents for eight straight years before being discovered.
