Randy shares a couple of his favorite papers with Jim: discussion about general relativity by engineer and science fiction author Robert L. Forward on how general relativity could be used in a terrestrial environment, including proposals for devices and materials.
Robert L. Forward on Wikipedia.
General Relativity for the Experimentalist in the Proceedings of the IRE (on IEEE Xplore).
Guidelines to Antigravity in the American Journal of Physics (Scitation.org) (alternate).
Previous shows mentioned:
G4V: The Gravitational 4-Vector Formulation of Gravity