ContentBuddy is a proprietary CMS system used exclusively for my clients, and websites myself and my organization build for our clients.
ContentBuddy solves an age old developer problem: Rapid site development. The CMS offers most of the same features that a system like WordPress or Joomla would offer, but it also gives developers more customization options, and flexibility to build their application. Clients also love it, because it eases the nerves of using an open source platform.
From a development standpoint, ContentBuddy runs as a standalone API, serving content to any other system in a JSON format. This flexibility allows it to be used to server literally any type of content to any type of site.