We love this project. Not only does it work for closet doors, but it's also an easy, low cost way to jazz up any small space. All you need is paint, posterboard, painter's tape, and a pencil.
This project was also the result of design blog collaboration. Benita from Chez Larsson painted her closet doors with orange trellis pattern. Then Courtney from Modern Homebody decided to do it at her house, and she put up a full tutorial.