I enjoy using rather than tossing my cardfront swaps after they retire. I can only use so many of certain types of cards, so I attach them to a white or ivory cardbase and donate them to Operation Write Home. The charity sends a box of cards to a contact who distributes the cards among their military unit/group for the hero to send a card home to a friend or family member. Cards written TO a hero are also included so that those who don't normally receive mail get one as well, but the main focus is cards for the heroes to send home.
If you'd like to read more about Operation Write Home, here is a link to their website: http://operationwritehome.org/