The future of flight may be electric air taxis.Efficiencies in battery technology are enabling massive transportation innovations, and not just with electric vehicles. Start-ups such as Archer Aviation (ACHR 2.98%) have developed electric air taxis, otherwise known as electric vertical takeoff and landing vehicles (eVTOLs).With taxis under testing and the promise to bring a new form of urban transportation to market, Archer's stock has soared, up close to 300% in the last three years alone. Today, the stock ...