You know how kids always want to touch things when they check something out? Well, birds always want to taste them. I'm not sure if they literally like to taste new things, but they use their mouths to interact with the world in the way we use hands. For touching, holding, and, well, checking things out. Peanut was pretty fascinated when I rolled the coins up. Nickels were his favorite. Click to see a bigger version. NOTE, though, that these days pennies have zinc in them, which is very toxic to birds. Particularly if your bird big enough to mar the metal with their beaks, don't give them pennies as toys!