I got a little bored with my themes, so I decided to make use of some experiments I still had floating around and try to turn it into a complete theme. Be warned, it's a bit of a mess and not quite finished, but I guess it's usable.
Aside from the mirage engine (which is not a complete engine, but only provides certain elements), you will also need ubuntulooks and murrine to use the included themes. I'll likely drop the murrine dependency at some point but ubuntulooks will stay, since I see no point in duplicating half of the code. With more and more cairo engines coming out, I believe this kind of code sharing makes a lot of sense.
Make sure to check bvc's metacity theme and modifications: http://www.kernow-webhosting.com/~bvc/theme/mcity/Mirage2.tar.gz