PSAD is a collection of four lightweight system daemons written in Perl and in C that is designed to work with Linux firewalling code (iptables in the 2.4.x kernels, and ipchains in the 2.2.x kernels) to detect port scans. It features a set of highly configurable danger thresholds (with sensible defaults provided), verbose alert messages [...]

Valgrind is an award-winning instrumentation framework for building dynamic analysis tools. There are Valgrind tools that can automatically detect many memory management and threading bugs, and profile your programs in detail. You can also use Valgrind to build new tools.
The Valgrind distribution currently includes five production-quality tools: a memory error detector, a thread error detector, [...]

Argus is a fixed-model Real Time Flow Monitor designed to track and report on the status and performance of all network transactions seen in a data network traffic stream. Argus provides a common data format for reporting flow metrics such as connectivity, capacity, demand, loss, delay, and jitter on a per transaction basis. The record [...]

As most of you probably know by now that a “Hacker” group called “Anonymous” has setup a project called “Chanology” to take down Church of Scientology. You can listen to their gripe about COS (Church of Scientology) and why they are doing what they are doing: http://www.youtube.com/watch?v=JCbKv9yiLiQ
They have also setup up a project page which [...]