ArchServer is a distribution of Arch Linux for servers. It is designed to be more stable instead of using rolling-release update methods.
The ArchLinux Development Stack provides a whole stack of applications needed to support development projects during their life cycle on ArchLinux servers. The packages include Nexus, Sonar, Hudson, and Redmine.
PlugUI is a sysadmin Web interface for small ARM-based devices running Arch Linux ARM. It will run on other distributions, but the package manager is geared to use pacman.
A high performance document database.
A social networks visualizer for Linux.