http://www.la-samhna.de/samhain/
Samhain is a multiplatform, open source host-based intrusion detection system (HIDS). Samhain provides file integrity checking, as well as rootkit detection, port monitoring, detection of rogue SUID executables, and hidden processes.
http://www.cs.tut.fi/%7Erammer/aide/manual.html
The beginnings of the manual for AIDE (Advanced Intrusion Detection Environment), the free replacement for Tripwire.
http://coppermine-gallery.net/demo/cpg14x/docs/index.htm#14
Upgrading Coppermine from version 1.4.x to the latest (as at version 1.4.12).