I’ve seen many differents bookmarks, magnetic bookmarks, wooden bookmarks and many other plain unexiting bookmarks. Now this one is really new and really has… a double function !
How it works? 
Simply put the Thumbthing onto your thumb and place into the spine of the book. The two wings will hold the pages open more easily, making reading more comfortable. No pain in your fingers any more.
It allows you to read with one hand only. It prevents the spine of the book from being broken.
I like the idea !!