Disney has announced that you can upgrade the free Magic Bands you get when you stay at a Disney World resort, or renewal your annual pass. At the moment, you get a selection of solid colours to choose from. But soon, you'll have the option to purchase from a selection of character Magic Bands for $14.99 off what they cost to buy outright. You can only take advantage of these upgrades 11 days before you're due to check-in.
Looking at Disney's video (embedded below) the Magic Bands you can upgrade to appear to be the ones available to buy for $24.99, which means the upgrade will cost $10.