@akuCRACKER, Ubuntu 6.06 is the Linux distro. The Theme being used is called GNOME Vista.
Download the Theme from here
There's only one Glass theme, the rest (translucency) is achieved by XGL.
Forget Baghira, there are better Themes!!!
When you extract the file gnomevista.tar.bz2. A directory would be created
by name Gnome-Vista, under that directory there is a file called HowToInstall.
That explains how to install this GNOME Vista Theme.
You need a good Graphics card to run XGL. To install & configure XGL Click here
Goodluck