libapache2-mod-scramble-ip is an Apache 2 module that works like mod_removeip, but instead of just overwriting the IP address with 127.0.0.1, it encrypts the IP address. This way you always get an IP address to work with (in scripts, etc.) and have the ability to use tools like awstats to analyze your logs. It's in alpha status, but working on some Apache 2 servers, and the 'cost' (load) should be small and reasonable.
When writing anything that needs to communicate with a terminal in some way, it is almost always speaking some dialect of VT100 or ANSI. The libvt 100 library aims solely at parsing a stream of VT100/ANSI data and then letting the host application do the rendering. Many other projects also parse VT100/ANSI data, but their parser is always tangled up with the actual rendering of the data, making reuse in other projects problematic. The hope is that other projects will start using libvt100 and everyone can stop reinventing the wheel with each project.
locust is a full featured Internet search engine specifically designed to power vertical search, enterprise search, or a knowledge area search applications. It can index 2.5 million documents per 24 hours on a single Dell server. It consists of clean C++/STL code written from scratch.
Log4php is a PHP port of Log4j, the most popular Java logging framework. It supports configuration through XML and properties files (with the same structure as log4j) and custom Configurators. File, RollingFile, DailyFile, Echo, Console, Mail, PEAR::Db, PHP error, Syslog or NT events, and socket appenders are supported. Simple, TTCC, Pattern, Html, and Xml Layouts are supported. It also supports Filters, custom Levels, and Loggers. Internal debugging can be switched on and off. Log4php can be used inside a class or inside a main/sub function.
Logfilter is a tool for performing ad hoc analysis on Apache log files. Logfilter is especially useful when you wish to find records matching very specific criteria, since you can specify exactly which fields to match. The tool also plays well in a Unix environment by accepting input either through files or via stdin.