Examples of future spacecraft include craft that use nuclear-pulse propulsion and other exotic methods of space travel. Project Orion, Project Daedalus and Project Longshot were proposals in the 1960s to build future spacecraft that could traverse the solar system with ease.
Continued advances in the strength of materials, nanotechnology and economic efficiency makes future spacecraft more viable than the stalled Projects Orion, Daedalus and Longshot. Back then, even the most advanced spacecraft designs required centuries to reach the nearest star, and the costs were prohibitive. Today, advances like carbon nanotubes reduce the mass and increase the strength of proposed future spacecraft, and new methods of propulsion are being explored.