Electric aircraft that don't require runways could make it easier to get around cities. The Lilium Jet, pictured below, is a five-seater aircraft that aims to start an air taxi service by 2025.
SpaceX is currently developing the Starship, a rocket designed to take humans to Mars and beyond. It can also be used to transport people around the Earth in less than an hour. Flights from London to Hong Kong, which normally takes 11 hours 50 minutes by plane, would take just 34 minutes with the Starship.