check out this site for things found in library books: www.bookbits.wordpress.com . i have read that one of the strangest things found in a library book was a piece of fried bacon. i have found: Q-Tips, a panty liner, prescriptions, pictures, blank checks, dollar bills galore, a ten dollar bill, CDs and DVDs, dental floss, drinking straws, an unlit match, toilet paper squares (lots of those), a pipe cleaner, bookmarks from around the world, pens, a single earring, a lot of airline tickets, very personal information (birth and death certificates, licenses, doctor's instructions, social security cards, w2 forms, checks of all kinds), used lollipop sticks, emory boards, used popsicles sticks, wrapper from an ice pop, stick of chewing gum and much, much more. nope...i did not keep any of the money. it went to the library (after a few months) donation fund.
instead of bookmarks, i am now using elastics to keep my place. they work really well as long as they are loose and do not crumple the pages or the cover and i never lose my place (unless the elastic breaks).
for non-Rhode Islanders: elastics=rubber bands