Apache Karaf is a small OSGi based runtime which provides a lightweight container onto which various components and applications can be deployed.  Amongst the provided features are: hot deployment, dynamic configuration, centralized logging system, provisioning, native os integration, an extensible shell console, remote access through a secured ssh channel, a security framework for authorization and authentication and more... Apache Karaf is the base container for a number of projects, including Apache Geronimo, Apache ServiceMix, Fuse ESB.

New to this release of Apache Karaf is a JAAS Database Login Module, a way to store passwords in a secured way, a mechanism that allows a karaf application to distinguish between UserPrincipal and RolePrincipal without depending from the Karaf JAAS Module.  The shell console has been enhanced to be available in a plain non-OSGi environment and smart tab completion has been improved, along with various commands. 
We have also resolved a number of outstanding issues, and improved support on OS X and IBM Java based systems. For more detail please see the release notes.

Karaf can be download at the following location.