Apparently, pin trading was introduced into the Disney parks, resorts and cruise lines in 1999 as part of the Millennium celebrations. This activity became so popular that it is now one of the biggest things happening in Disney places around the globe! You can Google pin trading to find out all about it, but here's a short version. You purchase however many Disney pins you want to start with. These have to be metal pins with a pin back (no brooch styles) that feature Disney characters, designs or affiliates on the front --- as well as having the Disney copyright info on the back. If your pins fit all that criteria, they are 100% trade-able! You wear your pins on a neck lanyard (available in all Disney shops and parks or online) or a hip sheet and can approach Disney employees or other guests with pins to offer a trade. It's pin for pin, no money or haggling involved. Disney employees always trade with you, since all those pins are supplied by Disney. Other guests have the option of trading or not trading, of course.
As soon as we arrived back home, we went online, ordered some lanyards (Chip and Dale lanyards) and found a really great deal on a lot of fifty starter pins. Those just arrived today, and we are SO EXCITED! Seeing them, it's totally obvious that fifty pins is not going to be enough, so I think that we're going to be working on making and selling some dolls or something to finance some more pins! We're planning one day at Epcot and a couple mornings at Disney Springs just for pin trading, so it's a pretty neat thing to be working on.