logsurfer is a log checking/auditing tool similar to swatch and logcheck but with the capability of handling multi-line messages and dynamically adapting the ruleset. It is written in portable C, well documented, fast, and flexible. It works on any textfile or stdin, can be run at intervals or continuously, and has timeouts and resource limits.
rt is an n-dimensional raytracer. It supports any positive number of spatial dimensions, color and grayscale, cylinders with an arbitrary number of round dimensions (spheres and cubes are special cases of cylinders), quadratic surfaces, convex hulls, regular polytopes, unions, intersections, cuts, extrusions, reflection, refraction, functional texture maps, portals into other traces, ambient light, multiple light sources, directional light sources, gamma correction, fish-eye effect, and output as PNG or PPM. It has been tested under DOS, Solaris, Digital Unix, FreeBSD, NetBSD, Linux, Ultrix, System V, and BeOS.
Netcat is a simple Unix utility which reads and writes data across network connections, using TCP or UDP protocol. It is designed to be a reliable backend tool that can be used directly or easily driven by other programs time, it is a feature-rich network debugging and exploration tool, since it can create almost any kind of connection you would need and has several interesting built-in capabilities.
Behemot Graphics Editor is a graphics program which allows you to model and render 3D objects and scenes. It can create and graphically modify b-rep, blob, NURBS models. It can also logically intersect or subtract objects, render text into solid objects, edit polyline and NURBS curves, build rotation and sweep solids and link objects into groups for easy movement. Complex animations and advanced modelling operations can be realized Prolog scripts. Customizable vector fields allow you to deform the model. It can export scenes in DXF or VRML format or animation in MPEG format, and import some DXF and 3DS files.
Par is a paragraph reformatter, vaguely similar to the standard Unix fmt filter, but better. It uses a dynamic programming algorithm that produces better-looking line breaks than the greedy algorithm used by fmt. It can also deal correctly with a variety of quotation and comment conventions.
Jetmon is a client/server NOC monitor tool, allowing light-weight applet in any browser to monitor network device reachablity information from a central server. It provides simple red-light/green-light indicators in a tiered display, with optional history and status windows, accumulative stats, and exteral URL links to MRTG-like pages, all from a single interface.