This theme is a modification of ubuntu 10.04 Radiance theme. I liked the original theme, but I don't liked the abrupt color change between the menubar and the main window.
I've created two modifications of the original theme without that abrupt change.
In radiance-flat-light theme I've changed the color of the menubar and metacity border so that they match the color of the main window.
In the radiance-flat-dark theme I've changed the color of the main window so that it match the color of the menubar. (I had to change also the color of highlighted items because the original one didn't look very good in the new theme...I used the orange color of the original ubuntu logo)
I like very much radiance-flat-dark theme, while I don't like very much the other one.. tell me your opinion..
tested on ubuntu 10.04
To have the breadcrumbs like the screenshots you need this hack http://gnome-look.org/content/show.php?content=127394