2. Character Meetings
On Disney's cruise ships, much like their theme parks, you'll often see some of your favorite Disney characters roaming around for photo and autograph opportunities. There's nothing quite like admiring the serene ocean view outside the hallway window, only to turn around and be facing Peter Pan or even Mickey himself!
In other cases you'll have to wait in line to meet a character rather than meeting them purely by serendipity, but it's always worth the wait.