Starling is a light-weight persistent queue server that speaks the MemCache protocol. It was built to drive Twitter's backend, and is in production across Twitter's cluster.
A easy-to-use, full featured, extendible content management system built with Ruby on Rails. Web 2.0 features including: rss, tags, ajax 'quick' editing, gmail style spell checker and overlays.
RubyForge is a home for open source Ruby projects