I recently saw this bookmark idea while browsing craft ideas online. (I can't remember where I saw it to give the appropriate credit, sorry!) Even though I use my eReader, I still think some of these will be handy. I am currently using one on my planner and think they could also be useful in cookbooks.
The concept includes a piece of ribbon, a button, and a hair elastic - - the end result is a book mark that doesn't slip :)