To get a copy of this library, submit a request to 0x6763.BitcoinCrypto@gmail.com It will be released as open source by mid July. BitcoinCrypto javadocs: http://x6763.github.com/BitcoinCrypto/doc/index.html The classes of interest when developing Bitcoin software with this library are: org.bitcoin.x6763.crypto.digest.Hash160 org.bitcoin.x6763.crypto.digest.Hash256 org.bitcoin.x6763.crypto.digest.RIPEMD160 org.bitcoin.x6763.crypto.digest.SHA256 org.bitcoin.x6763.crypto.ecdsa.KeyPairGenerator org.bitcoin.x6763.crypto.ecdsa.PrivateKey org.bitcoin.x6763.crypto.ecdsa.PublicKey org.bitcoin.x6763.crypto.ecdsa.signers.ECDSASignature