Xfce

Xfce is the Cholesterol-Free Desktop Environment.

Xfce is a desktop alternative to the popular GNOME and KDE environments. It is a GTK-based environment, like GNOME. It emphasizes speed and small size over features, though it is much more feature-rich than a bare-bones window manager.

XFCE-Desktop

XFCE Forum

XFCE-Wikia

ArchLinux XFCE-Wiki-entry Good information on setting up XFCE.

XFCE-Look Themes, Wallpapers etc