Here's a gadget that might be worth adding to the traveler's flight bag. This allows for usb power from the audio out on handrest. Price is about $35.

Inflight Power Recharger Cables

Here's some neat software that optimizes your ride visits at Disneyland, or Disneyworld. For roughly $20 you can plan out your ride plan. Definitely gonna buy this the next time we go to Disney World.

RideMax - Spend Less Time in Line at Disney's Theme Parks