Lets say I have 4gb of t.v. shows in my Movies folder. Time Machine backed up the files and knows that the files are there. Now say I want to move the 4gb of files to new folder called "TV" and Time Machine backs this up. It now has backed up the 4gb of files twice. Once in the Movies folder and once in the new TV folder (on the external drive). Now lets say I want to move them again into a new folder. Time Machine will back this up in their new places now. Keep in mind I'm simply moving the files around on my computer, not copying them to these new folders. So on my external hard drive there will be 12gb worth of the same tv shows that only add up to 4gb on my computer since I moved them three times. So every time I move a file to a different folder Time Machine will back up another copy of it. This to me is going to chew up my external hd drive faster then I thought. I have tons of big video files that I'm moving around and all along time machine will be adding on copy after copy of the same file, eating up space on my ex hd. I tested this and it seems to be correct. So in order to consciously save space on my external hd i'll have to have the foresight to create a folder and just keep the big files on there and not move them. Or only back up once a day, which kinda blows since I like having Time Machine running in the back round for peace of mind. This is kinda annoying. I have plenty of extra space for now, but when I finally do run out of it I'll know why and its not gonna feel good. Anyone else think of this? Am I wrong? Or have any ideas/input/comments?