My first job out of college I worked as the librarian at an interior design firm. There were a hundred things I loved about that job and one of them was watching the designers put together their boards. They would gather fabric swatches, paint chips, photographs, and any textural elements that fit their concept to pull together a presentation/inspiration board for the client.
Some of those boards looked like pieces of art when they finished- after all, they were created to show the clients the beauty of the designer's vision.
I know the idea of the inspiration board goes beyond interior designers and can be found in all aspects of the arts. I still think they are pretty amazing little planks of creativity.....
