What is the best way to smart backup a 120GB and growing folder to a portable hard drive? I have a 250 WD portable hard drive and i would like to backup my TVshow/movies folder so that i can have a full backup when i use my laptop. All the files are in one folder on my desktop, i add a movie every 1-2 days and a tvshow (from my dvr) daily. Right now i just drag it and drop it to my portable hard drive but that takes to long. The perfect thing would be something like time machine only for that folder (without the going in time). Thanks.