Something that might be a good gift to the beginning and advanced prepper is the BATTERY BANK VIDEO by Steven Harris. Another idea long that line is if you want to make something unique give a MP3 Player loaded with The Survival Podcast episodes. Battery Backup Part 1 and Battery Backup Part 2might be a good start.
Other power ideas include:
A hand crank light is another good idea.
Energizer Weatheready 3-LED Carabineer Rechargeable Crank Light, Red