Need some creative ideas..?

I have acquired a whole bunch of these transparent, plastic, flexible, bookmark sized things with various anime, vocaloid, etc. characters printed on them. I was wondering if anyone had any ideas as to what I could do with them, I highly doubt they have a specific purpose. They are transparent and have a glossy side to them so they look a lot better on white than anything else. Aside from using them as bookmarks or simply taping them to a paper and sticking it in my binder (which is what I plan on doing if I don't get any good ideas), what could I do with them? :) Any help would be greatly appreciated. Thanks~