Option 2: Find out where the book mark is and go looking for it.
But why?
NamelessleTTer is a collaborative art project where people from all horizons leave personalized bookmarks in books with the goal of seeing other readers discover them.
All kinds of bookmarks are accepted (creativity is the limit). They can be left in different places such as libraries, schools, etc.
The goal is to provoke curiosity (to encourage people to visit libraries in hopes of discovering one of these bookmarks), to bring a new and exciting aspect to book reading in a world that is becoming increasingly digital, and to interact with other people.
More details here.
Left in Where Is God When It Hurts?
Left in Hands Up Miss Seeton