In Sheena Calvert's Graphic Design School: The Principles and Practices of Graphic Design, designers keep a notebook for each project, saving clippings, prototy

In Sheena Calvert's Graphic Design School: The Principles and Practices of Graphic Design, designers keep a notebook for each project, saving clippings, prototypes, and the like as they converge on the final design. That's per client, and I'm not sure it's all necessarily shared. For web designs, I wonder if inspiration is kept in a Powerpoint of screenshots, for example--or a folder with files. For the latter approach, Mac OS Finder supports file preview to flip through ideas.