As a spacialist who works primarily in small New York City apartments, I am constantly aware of how hinged doors take up valuable real estate -- particularly closet doors. They need a lot of floor space for clearance. I sometimes recommend that clients remove their closet door(s) and leave them as is or add a curtain. For those who want to make an investment in aesthetics and be au courant, I suggest they consider barn doors.
Not all barn doors are rustic. In fact, they can be very sophisticated with a modern flair. They are easy to install. Hardware can be purchased online.
Barn doors are not just for closets. They can be used anywhere there is a traditional door -- bathrooms and bedrooms -- or to close off open areas such as kitchens and laundries.
For ideas on how to replace your hinged doors, google "modern barn doors - images".
The Clutter Whisperer of New York City
Master Spacialist, Declutterer and Stager