I have an envelope full of ephemera from a recent trip to Germany. During a 6 week stay there, I held on to the subway tickets, museum stubs, maps and even some postcards I couldn't bring myself to send. Unless I choose to glue these into a scrapbook, or collage them onto the cover of a book, they will sit in the envelope, eventually growing meaningless.
I'm sure most people think of books as a way to capture thoughts or protect precious stories. But, incorporating travel mementos is a way to create something useful from a nostalgic scrap of ephemera. Coins and other collected items can be inlaid into the surface of a book: shells, pebbles, sea glass, a small skeleton key. Paper and other textiles can be used to cover books, as end papers, or even incorporated into the text block.