Apologies for pulling this old thread out of the grave, but rather than start a new one, I figured I'd tack some news onto the best one related to Zerocoin. I just checked their web site and it says that prototype software should be available in mid-to-late June: http://zerocoin.org/software Pretty excited! I want to play with it. Hopefully it will be in production use on the bitcoin network by the end of the year.