Midgard keeps chugging along
The open-source CMS package Midgard is not very popular in North America, but it sports a wide following in Central and Eastern Europe, including a core group of developers who have slowly re-architected the package after a semi-dormant period early in the decade. Midgard uses PHP and MySQL (nothing unusual there) and ships with some special Apache webserver modules for performance (that's novel). The latest release (1.7.6, in case you're counting) builds on some previous attempts to make the package play better in standard corporate environments, including integration with Apache Lucene for search, and JSR-170 support as well.