Epidermis theme manager is an open source GTK application for managing, automatically downloading and installing themes of various types, in order to transform the look of your Ubuntu desktop, from the moment you turn it on until the moment you turn it off. Take a look at the screenshots.
An Epidermis skin handles the following themes, called pigments:
Planned pigments include Emerald, Compiz Fusion, Qt, etc.
Epidermis uses a similar functionality to package repositories, all the customizations, or pigments, are stored in an epidermis repository and are easily downloadable and installable. Creating a new skin is simply a matter of choosing which pigments to link to. Skins can share pigments, just like packages can share dependencies.
The code is in Python and PyGTK and released under GPLv2 open source license, and is hosted on Launchpad.net.