Advanced Web Statistics (AWStats) is a free powerful Web server logfile analyzer (Perl script) that shows you all your Web statistics including visits, unique visitors, pages, hits, rush hours, search engines, keywords used to find your site, robots, broken links, and more. It works with both IIS 5.0+ and Apache Web server log files as a CGI and/or from the command line. It also supports around 40 languages.
AirSAM is a desktop GUI that compliments the Web based Snort Alert Monitor. AirSAM gives up to date insight into who might be attacking your network. The ultimate goal is to give audio/visual cues right at the time of the attack. AirSAM is an Adobe Air application and should run on Mac OS, Linux, and Windows.
AlarmMon is an alarm monitoring system for TCP/IP networks. It consists of an "alarm" client, an "alarmsvr" server, and several agents that work with a central registration database. It can track the status of verious services, including BIND, Sendmail, and modems, and send notifications by email, SMS, or pager.
Analog PHP is a short and simple logging package for PHP 5.3+ based around the idea of using closures for configurability and extensibility. It functions as a static class, but you can completely control the handling of log messages through closures (aka anonymous functions), and it also comes with a dozen pre-written handlers. It is well-documented, with examples for each type of log handler, and ultra-concise. The core is literally only 43 lines of clear, non-obfuscated code, and the whole is only a fraction of the size of comparable packages (for example, 293 total lines vs 1021 for Monolog).
Synapse is an ESB engine and XML router built completely on open standards. It is a mediation framework for XML messages and Web services that allows messages flowing through, into, or out of an organization to be mediated, including aspects such as logging, service lookup, performance mediation, versioning, failover, monitoring, fault management, and tracing.
ALF is a native logging framework for Java with the unique advantage of supporting automated method tracing. This platform-independent library allows developers to debug their applications quickly without adding any code. By simply adding an argument to the JVM, you will get immediate method tracing, which can be filtered by package or class and sent to the console or a file. You can also use the ALF logging library to integrate information, warning, error, or exception statements into the output.
Avast-ng gives you the ability to sift through vast amounts of log files and display current syslog data which is useful to you. It sifts out all the normal flotsam in your log files, and just displays messages which you have defined to be either out of the ordinary or unexpected. With its built in query builder, you can build new filters to include or exclude log messages quickly. It uses a nifty, intuitive AJAX interface. You can save multiple filters for quick access. Avast-ng continuously monitors your syslog messages, showing the most current messages matching your filter.