Question for my tech people. I'm on a mac and wondering if there's a way to create a backup that only adds new or changed files to the backup system, but never deletes any files from the backup. In other words, if I create the backup today, and then delete 50gigs of files from my comp harddrive, and then later backup the newly cleaned drive, is there any way it can copy new or changed files to the backup, without reflecting the fact that I've deleted a chunk of files from the source disc (i.e. without deleting those files form the backup)? It kind of sounds like I want to create a 'cumulative' incremental backup. I only want files to be added or changed, never deleted. So, new files would be added, changed files would be copied over, and deleted files (deleted from the source drive) would be left alone on the backup.