When I see sliding interior barn doors it reminds me of my old apartment in San Luis Obispo when I was in college. It brings back good memories :-)
My apartment complex consisted of three level apartments in which the top level was a lofted room. That room was mine complete with ladder and sliding door. And no I never fell off, almost did a few nights though ;-) It was pretty much like the tree-house I always wished I had.
Barn doors inside add something unexpected and are way more interesting that the traditional door with hinges. I'm a sucker for the rustic look of natural wood. But adding a bright color door can liven up a room and make it look more modern.