George Hotz, aka geohot, who joined Twitter on November 18 after Elon Musk's "extremely hardcore" pledge, resigned, saying he could not make "any real impact" (Jay Peters/The Verge)

Jay Peters / The Verge:
George Hotz, aka geohot, who joined Twitter on November 18 after Elon Musk's “extremely hardcore” pledge, resigned, saying he could not make “any real impact”  —  George Hotz, known for being the first person to carrier-unlock an iPhone and jailbreaking the PS3 …