RSA Data Encryption is currently running a challenge to illustrate the security level of encryption as the key length goes up. Most of the challenges use their RC5 encryption algorithm, which has a flexible key length, and one used DES. 4 of the challenges have been broken, RC5 40 bit, 48 bit, and 56 bit. The DES (also 56 bit) challenge has also been broken. The 64 bit challenge is being attempted by distributed.net (see http://www.distributed.net) and there are no other known coordinated efforts to crack the 64 bit key. See http://rc5stats.distributed.net and http://home.pacbell.net/cwax/rc5-64.html for information on the progress of this effort.
The claim is that the RC5 64 bit challenge will be cracked before midnight GMT January 1, 1999. RSA Data Encryption's announcement of the date and time the correct key was submitted to them will be considered to be the date and time of when the challenge was cracked. YES coupons will return 1 if the challenge is cracked by the deadline, and 0 if it is not.
Just to be clear, the range of times during which the challenge must be broken for this claim to be judged true extends until the end of 1998 GMT.