I have an external that I use with Time Machine, however I don't need incremental backups. Rather, what I would like is only one backup so that I can save space. In this backup, however, I would like specific things to change that change on my computer, as TM already does with its incremental backups. So basically I just want to condense the function of TM into one single backup that will update whenever I back up again. I realize this is not the primary function of TM, but is there any way to make this possible? Or is there any other software that would do this? I've heard of Silverkeeper and Retrospect, but never used them.