A new vision for the city of the future by Alex Konrad @FortuneMagazine January 4, 2012, 10:50 AM EST E-mail Tweet Facebook Google Plus Linkedin Share icons As the world population expands, cities will have to transform to meet the challenge. Here come foldable cars and flexible apartments. A small vehicle that looks like a Jetsons version of a smart car rests in a room at MIT’s Media Lab. Here’s how it works. When parking, the rear of the electric CityCar slides under the chassis, allowing the body to fold up into a compact shell. Once folded, the CityCar will fit into a space just one-third the size of a standard parking spot. A single door on the front of the car pops open, allowing the driver to step out onto the sidewalk. The CityCar is just one example of how MIT’s Changing Places group envisions the urban lifestyle of 2022. In October the world population hit 7 billion, and now for the first time in history more than half of the world’s population lives in urban centers. MIT is studying how to house and move all those people in ways that will make urban living still bearable. Says Kent Larson, the program’s director: “We’re focusing on more efficient uses of resources, on ways to lower costs and energy use and at the same time increase personal space.” Larson sees the CityCar, for example, as fitting into the shared-use programs already gaining traction through companies such as ZipCar ZIP and Getaround. The cars would complement what he hopes will be a full system of sharing, from bicycles and scooters for shorter commutes to cars for longer jaunts. A prototype of the CityCar built by MIT and the Spanish company DenokInn will be unveiled at European Union headquarters in Brussels this month under the project name Hiriko. MIT’s Media Lab is also working on what it dubs the CityHome. Again, greater flexibility is key. The CityHome concept takes a Murphy-bed approach. A bedroom can double as anything from a kitchen to a personal gym with stoves, fridges, and StairMasters swinging out from hidden panels in the walls. Larson says that the customization cost for a small apartment would be as much as $30,000. However, the savings of paying for a one-room studio that functions as a three-room apartment could be 10 times that amount. MIT hopes to launch pilot programs in the Boston area. The system can be customized to fit different income brackets. Want a Sub-Zero to pop out of your wall? The benefit for real estate developers is that they can stack more units into each building. The biggest hang-up for adoption? Parking spaces for the denser housing. The problem is solved — surprise — by matching the CityHome with the CityCar. More from Fortune’s guide to the future Introduction Why Ryan Seacrest (For real!) is the future of media 4 new ways to solve the energy challenge The hot tech gig of 2022: Data scientist Brave new work: The office of tomorrow The workforce of the future: Older and healthier 4 zany futuristic ideas that could come true This article is from the January 16, 2012 issue of Fortune.