BitNami RubyStack provides a fast, easy way to develop and deploy Ruby on Rails applications. It includes Ruby, Subversion, MySQL, SQLite, ImageMagick, and several Ruby Gems, and will optionally install Apache 2.2 with rewrite and proxy support. It supports Windows, Linux, and OS X, so you can share the same Rails environment on multiple platforms.
Elektra is a universal hierarchical configuration store, similar to GConf and the Windows Registry. It allows programs to read and save their configurations with a consistent API, and allows them to be aware of other applications' configurations, leveraging easy application integration. While architecturally similar to other OS registries, Elektra does not have most of the problems found in those implementations. Elektra includes a library, an API, and commandline and GUI tools for administration tasks.
Facter is a simple cross-platform library for determining basic facts about an operating system, like the operating system name, IP address, or MAC address. It supports multiple mechanisms for resolving a given fact, and these mechanisms can be restricted to only working on specified operating systems or operating system releases.
Berkeley DB XML is a native XML database engine for use within your product. Made available as a C++ library with language bindings for Java, Perl, Python, PHP, and Tcl, it integrates directly into your application (it is not a standalone database server). It provides XQuery access into a database of document containers. XML documents are stored and indexed in their native format using Berkeley DB as the transactional database engine.