Amazon wants a key to your house. I did it. I regretted it. The Post's Geoffrey A. Fowler tests Amazon Key, a new service that allows Amazon deliverers to open your door with digital key. (Video: Jhaan Elker, Geoffrey Fowler/The Washington Post) I gave Amazon.com a key to go into my house and drop off packages when I’m not around. After two weeks, it turns out letting strangers in has been the lea