Arachnida is an embeddable Web server. It uses the OpenSSL library and consists of a small framework for networking that allows you to asynchronously accept and handle connections using a "new connection handler" to handle new connections and a "data handler" to handle incoming data. This makes it possible to add support for any TCP/IP based protocol by just adding a handler. A test suite is included.
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.