Argus is a system and network monitoring application. It will monitor nearly anything you ask it to monitor (TCP + UDP applications, IP connectivity, SNMP OIDS, etc). It presents a clean, easy-to-view Web interface. It can send alerts numerous ways (such as via pager) and can automatically escalate if someone falls asleep.
AFT (Almost Free Text) is a document preparation system. It is mostly free form, meaning that there is little intrusive markup; AFT source documents look a lot like plain old ASCII text. It has a few rules for structuring your document, more to do with formatting your text than embedding lots of commands, and it produces all types of output (HTML, XHTML, LaTeX, roll-your-own XML, etc.). All that needs to be done is to edit a rule file. You can even customize your own rule files for specialized output.
Email sends email to remote SMTP servers via the command line, which makes it useful in cron jobs. It will send to any RFC standard remote ESMTP server, is TLS/SSL enabled, and will allow you to encrypt, sign, and design your message on the fly. It has the capability to use signature files with dynamic options, address book functionality, and users can also attach pictures, binary files, documents, or whatever they want. It is completely compatible with GNUPG for encryption and signing, and is easy to configure and use.
mod_log_sql (formerly known as mod_log_mysql) is an Apache module that enables access logging to an SQL database. This capability can replace or coexist with Apache's regular text-file logging mechanisms. The currently supported database backend is MySQL, with PostgreSQL and others in development.
CGI::Application is a Perl framework intended to make it easier to create sophisticated, reusable Web-based applications. This module implements a methodology which can make Web software easier to design, easier to document, easier to write, and easier to evolve. CGI::Application builds on standard, non-proprietary technologies and techniques, such as the Common Gateway Interface and Lincoln D. Stein's excellent CGI.pm module. CGI::Application judiciously avoids employing technologies and techniques which would bind a developer to any one set of tools, operating system, or Web server.
Anti-censorship tools (proxyTools) consists of a huge Perl application (localProxy) and a set of tools to analyze the user's network (proxies, firewall rules, name servers, etc.). LocalProxy abstracts external services in an uncensored, reliable, fast manner to the localhost, where they may be used by standard clients (Web browsers, Usenet news clients, SOCKS-capable clients, etc.). Various combinations of strategies are tried to ensure the non-censored nature of the information, and multiple, parallel services (e.g. HTTP proxies) are used to ensure reliability and speed. The tools are capable of automating collection of the data required for localProxy. LocalProxy builds a configuration for the user and dynamically adjusts to using the fastest strategies and proxies available to it. The tools are useful for network analysis (firewall rules, proxy capabilities, etc.) independently of localProxy.
Apache::Gallery is a mod_perl handler that sits on top of your DocumentRoot and creates an image gallery of the files and directories there. It creates an thumbnail index of each directory and allows viewing of pictures in different resolutions. Pictures are resized on the fly and cached.
The HTML::Template module attempts to make using HTML templates simple and natural. It extends standard HTML with a few new tags for variables, loops, if/else blocks and includes. A file written with HTML and these new tags is called a template. Using this module you fill in the values for the variables and loops declared in the template. This allows you to seperate design (the HTML) from the data, which you generate in the Perl script. While there are many other HTML template systems available, this module is simple and fast. It doesn't try to reinvent Perl CGI, it just augments HTML with a few new and very useful abilities.