The Cap’n Crunch Bo’sun Whistle, in all its glory. Photo courtesy of Jeff Dilbert

Cereal companies have long used box prizes as an inducement for children to nag parents into buying sugary breakfast food. From movie tie-in toys to video games on CD-ROM (remember Chex Quest?), cereal box baubles tend to be momentarily thrilling and then quickly forgotten. Except when they’re used for hacking.

Only one cereal box toy has that distinction: the Cap’n Crunch Bo’sun whistle. Meant to replicate the whistles used by sailing officials (boatswains) to signal mealtimes or commands, the multicolored whistles came along with boxes of Cap’n Crunch starting in the mid-1960s. One fell into the hands of John Draper, a former U.S. Air Force electronics technician. Draper was part of an underground culture that predated hacking as we know it: phone phreaks. These early hackers played certain tones through their telephones to bypass AT&T’s analog system and get free long-distance phone calls.

Draper heard about the whistle from other phreakers. The whistle easily played at 2600Hz, the perfect tone to, in Apple Inc. co-founder Steve Wozniak’s words, “seize a phone line.” Though many phreakers used instruments for the same purpose, the mass-produced whistle became iconic. Draper became known for using it, and gave himself the nickname “Captain Crunch.” He even built devices, called “blue boxes,” to replicate that tone and other useful ones. After a story about blue boxes was published in Esquire in 1971, the then-college student Wozniak and his friend Steve Jobs tracked Draper down to learn all they could. (Though Wozniak admired Draper, he was intimidated by his intense energy, disheveled state, and many missing teeth.) The boxes could also be used for mischief. Wozniak tried to prank-call the pope, while Draper boasted that he once got President Nixon on the horn.

Jobs and Wozniak’s first joint-business venture was selling blue boxes to aspiring phreakers. “I don’t think there would ever have been an Apple Computer had there not been blue-boxing,” Jobs later commented in an interview. Captain Crunch himself has swung between fame and infamy—Draper spent time in jail for toll fraud, but later also wrote software used by IBM and Apple. While hailed as a hacking and software pioneer, Draper has also been accused of sexual harassment at conventions where he’s been invited as a guest.

Today, both Cap’n Crunch whistles and blue boxes are historical objects. A collection of the whistles are displayed at the Telephone Museum in Waltham, Massachusetts, while the Computer History Museum in Mountain View, California, has one of Wozniak’s handmade blue boxes. Though thousands of miles apart, both physically and technologically, they’re reminders of the connections between hacking, computing, and cereal.

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