Also , if I did make a centralized blind mix (which I probably wont as I imagine Zerocoin will become a standard), I would certainly not do it as kmfkewm. Nobody wants their project to be linked to international drug smuggling, and nobody wants to advertise their project to criminals. There is a bit of a disconnect between the communities that are widely adopting these programs and technologies , and the communities that are developing them (with a few exceptions, I2P and Bitcoin being the first that I think of). If PGP was advertised as a way for drug smugglers to secure their communications, it would not be good. And if the creator of RSA said that an implementation of it could be bugged, and then released the mathematical formulas behind it, it would be a big mistake to avoid using those formulas simply because of the fact that they could be used in a bugged implementation. At the core of the matter, what the Zerocoin guy said really should be obvious to anybody. Of course they can put a backdoor in for law enforcement. The second half of what he said is equally as true: of course if they put a backdoor in an open source project, nobody is going to use it. If they release the specification and it is good, but the code they release is backdoored, somebody will make Blindcoin , something that is identical to Zerocoin but without the backdoor. I really do hope that it is widely added to Bitcoin clients, of course providing that they have managed to create a cryptographically secure design. If their design is good and it is not integrated into all of the major Bitcoin clients, I will be really disappointed, and the Bitcoin developers community will have pissed away an opportunity to actually add strong anonymity to Bitcoin, something that it is currently lacking in and which needs to be glued onto it via third party services. Actually integrating that anonymity into the base protocol would be great for everybody, and a huge victory for us especially (although don't count on any of the people trying to get it implemented to mention this last point).