Columns, the University of Washington’s alumni magazine, writes on UW CSE’s Vanish project:
“The Vanish program encrypts a message, breaks the encryption key into many tiny pieces, and then sprinkles these pieces throughout a large peer-to-peer network that consists of more than a million computers all over the world. As individual computers leave the network and those that remain purge their memories, pieces of the key are gradually lost. Once a certain number of pieces are lost, the key can never be reassembled and the message can’t be decrypted.”