In the "not-sure-if-serious" category we have this plan to deliver gifts by drone. By far the biggest hurdle will be regulatory. Several groups have been trying to get permission for drones to fly in US airspace, not the least of which being the US military, but the FAA so far has insisted on a case-by-case approval system that is very slow and expensive. Not to mention the hobbyists who would probably order a bag of pencils and then wait in the front yard with a net gun.