Keepsake

"A little souvenir I hung onto... just in case."

- Cortana

A keepsake, memento, or souvenir is a unique item that a person holds to be of special importance, reminding them of a person, place, or event. They range from photographs, toys, trinkets, and other memorabilia. Many are kept out of memory of the person who gave it or originally owned it. Being personal objects, they are mostly unrecognizable to outsiders. Within the military, soldiers often pass along their dog tags as keepsakes for their comrades to remember them by.