What does the future hold? Obviously there is OGR-28 so you can continue to contribute as before (with the same client as for OGR-27). If you are still participating in the RC5-72 effort, please stop. It has become counterproductive for a number of reasons. First of all, besides the fact that the challenge has officially been dropped by RSA Labs themselves almost 7(!) years ago now, there is also the inescapable zeitgeist: the Snowden revelations have confirmed that RSA has accepted $10 million from the NSA [url]https://en.wikipedia.org/wiki/Dual_EC_DRBG [/url] to secretly include a backdoor in their products as early as 2004 and therefore taints the company and any ongoing promotion through continueing with an RC5 effort. This is diametrically opposed to the original intent of their own challenges.