Julian Assange and WikiLeaks have distributed hundreds of gigabytes of heavily encrypted "insurance files" over the years that contain an unknown amount of unreleased material. Assange historically claimed that these unreleased troves serve as a "thermonuclear" dead man's switch: if WikiLeaks or its personnel were permanently incapacitated, the decryption keys would be released to make the full, unredacted contents instantly public.
McAfee's "Dead Man's Switch": Prior to his death in a Spanish prison in June 2021, John McAfee frequently claimed to possess over 31 terabytes of incriminating, encrypted data on government corruption. He alleged that this information would automatically leak via a "dead man's switch" if he were ever captured or killed.