In a modest restaurant on the outskirts of Cairo, paid receipts are pinned to one of the walls, allowing hungry people who have no money to use them to order a sandwich.
The restaurant has joined the "Sandwich on the Wall" initiative that was launched by three young Egyptian students to provide poor people with free food. The idea is that a customer buys a sandwich and pays for another one; a hungry person who can't afford a sandwich can take the receipt from the wall to pay for a meal.