Have you seen these, 3.5 readers? Sticky back buttons. Put them around your house. When you’re out of detergent, paper towels, gatorade or what have you, just press the button and Amazon will charge you and send you some.
Super convenient or the start of the rise of the machines?
Could this work for self publishers? Every author sends their fans a button. Push it when you’re ready to buy the author’s next book.