There is a big difference between two dimensions and three dimensions. In two dimensions, you are pretty confined. Two lines intersect in general. In space, two lines have positive distance in general. Simple closed curves can form loops which are knotted etc. People therefore have always dreamed from flying cars. It is one of the predictions of science fiction which never materialized. Futurologists did not see the obstacles or the danger of having a freeway in the sky. Flying cars exist already. Here is an other one:

This week at the Farnborough International Airshow, Parajet is showcasing the SkyRunner to potential aviation distributors with a price tag of ,000. The design combines an all-terrain vehicle with a light sport aircraft capable of soaring 15,000 feet at a speed of 55mph, with a flying time of three hours. Powered by an innovative low-carbon petrol engine, the hybrid is presented as "the next generation of recreational aircraft...designed primarily to make aviation easily accessible and fun." The vehicle has undergone testing over five years, including a voyage from London to Timbuktu flown by inventor Gilo Cardozo. It builds on the motor design of the company's signature product, a propeller-powered jetpack already established on the market.