No need to explain why going "paperless", whenever possible, is important to help do our share of protecting the environment.
So instead of buying a ton of imported postcards, magnets, and snow globes in every place I visit, I create my own personal and absolutely digital, "Green" souvenirs.
How? I take panoramic pictures of interesting places, landmarks, local company signs and their logos. Then, use the letters from logos and signs to create the name of the city and the panoramic images to create the background.
Like any collection, mine has a storage too. On Instagram.