The pins are just another collector's item. They come in all types, based on characters, attractions, resorts, special events, etc. Many are limited editions with only a certain quantity made, whereas others are made in mass quantities. Guests can trade them with CM's one for one, or other guests - but many guests who collect them aren't as accomodating as the CM's have to be. At Disney pins can run from about $6.95 up to $14 or so. Pins are sold all over the "world" - and the largest single pin store is at DTD, called Pin Traders, and is opposite OUAT and Earl of Sandwich.