Hi all, I'm sorry if this is off topic here. I'll send this one anyways, but do let me know if you are interested in related project's release announcements so that I don't spam this list unnecessarily in the future. rsyncrypto is a utility that encrypts file in a rsync friendly way. Small changes to the plain text file will result in small changes to the cypher text file. The encryption takes place as a preprocessing step to rsyncing the content, and is performed entirely on one side of the connection. The other side need not have any method to decrypt the files at all. The encryption used is AES with any block size (256 bits by default), and the file key is encrypted using RSA. The encrypting machine need not have the RSA private key in order to prepare the files for rsyncing (encryption). It can also perform decryption without the private key, assuming meta-information (stored in a different file) is not lost. If this meta-information file is lost, it can be recovered with the use of the RSA private key. rsyncrypto uses the same basic method used in gzip's "rsyncable" patch to restart blocks from the original IV, thus localizing plain text changes in the cypher text. Version 0.02 is still marked "alpha", though it has passed regression tests, and is fairly reliable in decrypting and encrypting the files. rsyncrypto is written in C++, and is available under the GPL. Please feel free to visit the project's summary page at http://sourceforge.net/projects/rsyncrypto. Thanks, and sorry about the noise, Shachar -- Shachar Shemesh Lingnu Open Source Consulting ltd. http://www.lingnu.com/