The Library of St. Leibowitz's Abbey.
Rod Dreher had an interesting post inspired by A Canticle For Leibowitz(you've read it--right? RIGHT? I'll pretend to ignore all "no" responses from heathen philistines).
His question is this:
[W]hich books [do] you think are the most important to convey to generations in the future who will have lost all knowledge of our civilization and what's important to know [how] to reconstitute it?
Well--how should we stock that library, folks?