[TUHS] Your Most Prized UNIX Artifacts?

[segaloco via TUHS]

As someone who has been quite attentive to the documentation situation with UNIX, I've managed to build out a pretty appreciable library of historic works.  Among my most treasured bits are my 3B20S Release 4.1 manual and Bell Labs copies of the Lions's Commentary.

What do folks have around that you're particularly thrilled to have among your UNIX-y possessions?

- Matt G.