A Japanese hotel is treating guests to some unusual amenities including self-parking slippers, tables and floor cushions. The slippers, tables and cushions are rigged with a special version of Nissan’s “ProPILOT Park”, which is autonomous parking technology. When not in use, they automatically return to their designated spots at the push of a button. All of them are equipped with two tiny wheels, a motor and sensors to drive across the guest room. Many of the world’s top auto brands are developing self-driving technology. Nissan plans to market a car that can drive itself on city streets by 2020.