General Relativity
From The Transhumanist Wiki
Gravitation by Kip S. Thorne, Charles W. Misner, John Archibald Wheeler, Kip Thorne, John Wheeler [ISBN: 0716703440] The telephone book. Very large and imposing, but well written. 1215 pages. 5.7 pounds. Light beach reading.
General Relativity by Robert M. Wald [ISBN: 0226870332] Somewhat less hefty.
