Fattal Hotels, Israel's leading hotel chain, are the first to jump on Instagram's new service, Instagram Direct, which allows users to share private photos with others.
The premise is simple: Stay at a Fattal hotel and share a photo of the hotel, and the hotel will send you a private photo. Share that photo with the hotel staff and you'll get perks, like a free massage. You also get entered in a chance to win a vacation.
Nice idea that makes use of ingrained behavior.