umld - from documentation: "UMLd is a daemon to control and manage UML instances running on a host system. UMLd provides an interface on a TCP socket, allowing simple clients to be written which allow individual UMLs to be managed by users or by an administrator." It is written in php, which is strange, but the code looks quite neat and readable, regardles of a single php file with 3000 lines. It's all split into functions that seel well documented and logical. I'm tempted to give this one a go, although my scepticism towards the php being the right tool for managing UML's is gigantic. It's everything else about this project that looks advanced and sensibly done and documented that makes me want to try UMLd.
uml for woody - This page describes how to make a new Woody filesystem for UML (see comments, and it seems like a proper procedure of what i tried to do and seemed to get it wrong at few steps (documented as BoostrapingBasicDebian). I would definitely recommend using these instructions. My notes might help as additional/secondary documentation.
UML and linux virtual bridging - Using Linux virtual bridging, User-Mode-Linux and Zebra for IP routing exercises. here's visual representation of this UML setup.
rootstrap - originally written to provide a facility for building filesystems for use with User-mode Linux, but can be useful in other applications as well. pbuilder stands for Personal Builder, and it is a automatic Debian Package Building system for personal environments. pbuilder aims to be an easy-to-setup system for auto-building Debian packages inside a clean-room environment, so that it is possible to verify that a package can be built on most Debian installations.