Victory is an amazing minimalistic GNOME / XFCE theme that is easily customizable so you can use whatever colors you want.
A new version was released today with many changes which include: re-themed panel, all menus have been themed - this includes the GNOME MenuBar, GNOME Main Menu, SUSE Slab, USP, mintMenu, Cardapio -, many Metacity tweaks and lots of fixes.
Here are some Victory theme variations:
You can find more screenshots, HERE. But of course, you can use whatever colors / icons you like.
The Victory theme requires Murrine from GIT (20100323 or newer) with GNOME 2.30 - this means it will not work for Ubuntu 9.10 Karmic users (and below). It is recommended to use Nautilus Elementary to get the nice breadcrumbs you see in the screenshot.
Optionally, you can also install the Moblin icons. In Ubuntu, you can install them via Ubuntu's repositories:
sudo apt-get install moblin-icon-theme
You can also use this modified Moblin Icon theme (but it doesn't play nice with the GNOME Panel - resulting in huge panel icons but you can fix it by merging it with another icon theme).
To fix the OpenOffice icons, there is a tweak included in the theme - see the instructions on Victory's Gnome-Look page (link below).
Download Victory GNOME / XFCE theme
Many thanks to Ubuntu Life for the Victory theme link!