The Disney Blog links to this story about a Disney Imagineering contest. The winning students featured in the article devised an RFID system that would track your movements through the day and offer a take-home DVD.
“Our idea was to create a video capture system throughout the park,” said Michaelidis, who grew up in Hyde Park. “To take still-frame shots — like photos of visitors with Mickey Mouse — and video footage of guests on various rides and turn it into a DVD of your day at Disney.”
If you volunteer, it doesn’t really count as an invasion of privacy.