Inertial propulsion systems.

Reaction-less centrifugal propulsion

Tolchin's inercoid.

Inertial propulsion systems are not very popular in our times. I've heard several years ago that NASA is interested in inertial propulsion - they tested some solutions with centrifugal and gyroscopic forces as I noticed in the web. If those rumors are true, NASA interest of such a kind of propulsion seems to be not complying with their technological achievements in jet and rocket propulsion. This is significant and simultaneously not glorious for scientist and researchers community of our world but it's true, that in entire twentieth century time, they unfortunately weren't able to create something better than jet and rocket propulsion. They were spoiling whole time for making better something what was already so low efficient that making better it, was only wasting time and economic nonsense. All the time they were under the significant influence of military services so the other aims besides military purpose research were blocked and omitted - maybe this is the reason that our civilization is now in critical point on its way to freedom from its own progress traps in which it was pushed by military planning and cold war. Scientists and researchers on field of propulsion technology useful in space could be working on inertial propulsion - surely until this time they should be able to achieve interstellar level of progress in this topic, but today thanks to this persisting deal we are still creeping in surrounding of our own planet without any real answer for deep space travel requirements.