Disney hotel guests are given a wristband with RFID called a "Magic Band." Your tickets can be uploaded to it to be used for entry into the theme parks, it links your photo account to the park photographers, you can choose to charge things to your room with it and - you guessed it - it serves as a room key.

Normal check-in to hotels is at 3:00 p.m., but if you are equipped with the Magic Band you can just drop your luggage off at the hotel and go enjoy the parks. A text message tells you when your room is ready, and you never have to wait in line at the front desk to check in. It's quite convenient.