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I put all my movies on an external hard disk. Only need to have the disk plugged in if I want to watch a movie. That's good enough for me.
That's my setup. If I wanted to watch a movie on the go and not lug around the external disk, I'd just copy over the movies I'd wanted to watch.

I do have a portable disk, though, which makes it easier to carry my whole collection with me.
 
Just delete all the albums and movies that you never plan to watch or listen to again. "Media hoarding" problem solved. ;)
 
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