My ID card: I got it when I first came to Oregon State and it's one of the worst pictures I've ever taken in my life. I carry it around everywhere because I never know when I'll need it but I hate showing it to people.
I chose my wallet to tell a story about because it seems like I can't lose it. I've lost it at Disney World and had an employee return it to me at the end of the night as I was walking out of the park. I've also lost it at the downtown Corvallis McDonald's.
I wear a necklace all the time which has a mandala on one side and the Marine Corps insignia on the other. The mandala represents an ancient map to the past and future or the more modern theorized Einstein-Rosen bridge.
I have a "spinny" ring I wear on my pinky that helps me with a bad habit of picking at my scabs. I lost it in high school, but found it again in a hole in the bathroom wall once my parents started renovating the house.