Some Security-Related Tidbits

While browsing on unix security topics, I ran across a few interesting sites containing interesting security tidbits. These tidbits could possibly serve nicely as additional layers of security on unix boxen...

• NOEXEC - Is a short-circuit library that introduces broken exec and system calls into your libraries on as as-needed basis. Prevents shell-escapes from the plethora of places they are possible. Haven't tried it, but looks interesting.
• sudosh - A recording shell meant as a companion to sudo, which records all I/O and timings to a log file, which can then be replayed by administrators for review. I've tried it. Very nice.
• Iron-Bars Shell - Is a restricted-access chroot jail that also limits what commands can be issues by users. Haven't looked at it in-depth, but deserves more attention...