Mephisto is a blogging platform, competitor to WordPress but on Ruby on Rails.
Radiant CMS is a simple CMS system built in Ruby on Rails. It has a plugin interface so it can be extended.
The web design / development company based in Pakistan behind Vator.tv and other projects.
Commercial, enterprise level ruby on rails hosting sold by the slice!
Ruby, Node.js and Clojure application hosting. Pricing is based on web and background workers. One node free.
CRM package from 37Signals, the people behind Basecamp and other Ruby on Railes goodies.
symfony is a powerful PHP framework. It has some very impressive scaffolding (CRUD interface) tools, is highly customisable, and designed for enterprise level programming. It looks good for crud related projects, perhaps not so much custom projects.