Graffiti is an RDF store based on dynamic translation of RDF queries into SQL. It allows you to map any relational database schema into RDF semantics and vice-versa, and to store any RDF data in a relational database. Since 2003, this RDF store was used as the primary means of data access in the Samizdat open publishing engine, and now it's released as a stand-alone module ready for use in other applications.
iExploder is like a fire hydrant full of bad HTML and CSS code to test the stability and security of Web browsers. It is available as a standalone Web server or CGI script. It continuously feeds browsers bad data in the hope that they will eventually crash. It is designed to run for hours, or even days until the browser crashes.
RWMA (Ruby window manager addons) is a modular wrapper around dmenu and dzen for adding various keyboard driven actions to (usually minimalistic) window managers, inspired by ruby-wmii. Its main purpose is launching programs and displaying notifications, but it can be expanded with plugins (for example translation, music player control, and volume control).
nessus-xmlrpc is a Ruby library for the Nessus XML-RPC interface. You can use it to start, stop, pause, and resume scans. It lets you watch progress and status of scans, download reports, etc. It comes with an example command line program that shows how easy it is to interact with the Nessus scanner.
XapianFu is a Ruby library for working with Xapian databases. It builds on the GPL licensed Xapian Ruby bindings, but provides an interface more in-line with "The Ruby Way"(tm) and is considerably easier to use. For example, you can work almost entirely with Hash objects, and XapianFu will handle converting the Hash keys into Xapian term prefixes when indexing and when parsing queries. It also handles storing and retrieving hash entries as Xapian::Document values. XapianFu basically gives you a persistent Hash with full text indexing (and ACID transactions).
BinBackup is a tool intended to efficiently back up a directory to a set of size-limited media like CD-Rs or DVD-Rs. It's goal is to distribute the contents of a directory to a set of media while using the space available on these media as best as possible, minimizing the number of media required for a backup. To do this, BinBackup uses a bin packing algorithm to decide how to partition the contents of a directory and where to put them.