I received an email from a mother and son from Columbia, who just finished reading Memoirs of an Imaginary Friend. She explained that it's a tradition in her country to sign the last page and date it when finished reading a book.
She sent me a photo of the last page.
I love this idea. What a perfect way to record a moment for posterity. What a treat for readers to land on the last page and have a record of anyone who has read the book previously.
I'm doing it. I'm going to teach my kids to do it. I think you should, too.