Backstory: This past weekend I traveled to San Diego for work. It's been a few months since I've travel and I've forgotten a key items that I normally purchase every trip such as dramamine and a recent copy of Inc or another recent magazine for the flight.
The Idea: A website where you can pick select items to get auto shipped to you a few days before your flight.
Deep Dive: You would build a simple "wish list" for someone to have sent to them before any flight. You would tap into their gmail and/or calendar to determine when their next trip is scheduled. Based on their location and shipping times, you would ship the box out so they would receive it a few days before their flight.
You could include items such as medicine, snacks and reading materials.
Validation: I made a bunch of expensive impulse purchases at the airport because I didn't plan ahead of time and purchase items that I normally take.
Monetization: Airport items are already overpriced, you would be able to have a higher margin on items to guarantee their delivery before the flight.