Apache's mod_rewrite provides methods to map values to attributes using the directive RewriteMap. One not so well known feature of mod_rewrite is to extend this functionality with internal functions, which can be defined in a seperate Apache module. mod_icpquery is an Apache-2.0/2.2 compatible module that extends mod_rewrite by internal RewriteMap functions. It sends out a request as a UDP query to a list of Unicast or multicast addresses. This query conforms to RFC 2186, also known as ICP, and can be handled by various HTTP-caching servers such as squid. A cache-server handling ICP should reply to an ICP query with an ICP response indicating if it holds the desired object in its cache or not. This information can be further processed by mod_rewrite using its superb regex rules.
jpt is a generic database toolkit. The package's main component is the libjpt library, which can be easily linked into C++ and C programs. A jpt database consists of a single sparse table, with an arbitrary number of rows and columns. The programming interface is simple, and the data structures are designed for fast random inserts and lookups.
OSD Monitors is a tool for those who prefer simple window managers and don't want precious screen space cluttered with panels, icons, etc. It uses the xosd library to display various textual monitors (clock, CPU usage, net, swap, disk, etc.) transparently at a fixed position on the screen. It has a very low memory and CPU footprint.
WMFS (Window Manager From Scratch) is a lightweight and highly configurable tiling window manager for X. It can be configured with a configuration file (made with LibConfuse), supports Xft (Freetype) fonts and is compliant with the Extended Window Manager Hints (EWMH) specifications.
Rap3 is an identity management suite with a Web-based interface. It allows management of common enterprise elements like companies, organizational units, roles, applications, and users. Using its connectors, it can provision all or part of its contents to directory servers and other databases.
PTRANS reads P5 and P6 (PGM, PPM, PNM) files, and performs Floyd-Steinberg dithering and scaling while only holding two scanlines of image data at a time. It can be used on gigapixel images while only consuming a small amount of RAM. It outputs P4 (PBM) dithered monochrome bitmap and P5 (PGM) grayscale images. It performs pixel interpolation and smoothing. Gamma correction and contrast curves may be set from the command line.