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.
Conary is a distributed software management system for Linux distributions. It replaces traditional package management solutions (such as RPM and dpkg) with one designed to enable loose collaboration across the Internet. It enables sets of distributed and loosely connected repositories to define the components which are installed on a Linux system. Rather than having a full distribution come from a single vendor, it allows administrators and developers to branch a distribution, keeping the pieces which fit their environment while grabbing components from other repositories across the Internet.
Apollo is an open-source developer test skeleton toolkit for Java Web Start/JNLP. It lets you turbo-charge Web Start apps without Web Start to speed up your compile/run/test/debug/goof-off cycle, avoiding the hassle of stuffing, signing, uploading, or downloading your jars every time you rearrange a comma in your source code.