Whoever hung up the Courtesy Phone really wasn't being very courteous.
UK not-for-profit Eggs for Soldiers built a life-size tank out of 5,000 cartons to help raise awareness for its upcoming March Fourth Help for Heroes Campaign.
Instructables user hanlin_y did the math and realized that alkaline batteries are one of the most expensive forms of power that consumers can use. So he/she/it came up with a solution to power your parts even if they don't come with an AC adapter. With a wall plug, wires, and bamboo strips you can run your electronics off the grid; saving money and the environment at the same time.