SilverStripe is a CMS and application framework based on PHP5 / MySQL that powers your medium-sized website.
- Friendly flexible back-end out of the box
- Complete design/template freedom
- Productive object oriented coding framework (PHP5 only)
- Open Source! :)
- Works with the Web 2.0 rather than fighting it (supports APIs rather than having a module for everything)
- Good at web standards and search-engine ranking