If you travel, then you know what it's like to sit in coach, surrounded by grumpy people you'd never voluntarily hang out with, and vice versa. What a great time to pull out your DS and begin shouting, blowing, and rubbing in suggestive patterns!
The Legend of Zelda: Spirit Tracks seems like it would be a great game to capture the wonder of traveling. Unfortunately, it also captures the wonder of making an ass out of you. Blowing into the mic is a frequent, necessary technique, and that's not the sort of thing you can do without causing a bit of a scene.