1. The successor to RC4. Key point: In order to promote RC5, RSA conducts contests that pay people if they can crack it. The first contest used a 56-bit key, took 212 days to crack by http://www.distributed.net/ using a total of roughly 1-million computers trying all possible 35,000,000,000,000,000 combinations. The message was "It is time to move to a longer key length.", and it was encrypted using the key 0x532B744CC20999. From Hacking-Lexicon