What cheap/free software is good for (incrementally or better) backing up a local drive to a network drive, with the ability to efficiently resume if the backup is interrupted (i.e. the connection is broken)?
I'm backing up a largish amount of data from my local hard drive to my XDrive with a ~700Kbps upstream.
I'm willing to consider lack of a 'smart resume' feature if absolutely no good programs exist that implement. Multiple programs working in unison are just as acceptable as a single backup program, as I can write a script to unify them all myself. I'm even willing to consider something that keeps extra local backup data to aid in a more efficient.
Features that are required:
*Incremental (or better) backup.
*rsync like bandwidth efficiency or better (rsync isn't used because it doesn't efficiently resume from an interrupted backup).
*Smart ability to resume if the connection is broken (i.e. it doesn't have to recheck all files to see where it left off).
Features that are preferred, but not required:
*Compression of uncompressed files before transferring them.
*Customization of the software with scripts to potentially implement these and other features.
*Rollback to a previous backup (think version control applied to arbitrary files).