Gravitomagnetic Effects - Introductory article by Gerhard Schäfer (Jena University) about the ways that rotating bodies affect spacetime (and hence the propagation of light and particles in free fall) in their vicinity. (July 30, 2004)
Inertia Manipulation Through Metric Patching - E+print which presents the exact solution for the stress+energy tensor of a spherical matter shell of finite thickness that will patch together different metrics at the boundaries of the shell. By David Waite. (June 2, 2001)