Ubuntu/Debian Linux: Cairo Dock is an app
launcher for Ubuntu and Debian Linux that closely
mimics the sleek look and feel of the Mac OS X
Cairo Dock works with or without OpenGL, and
makes for a surprisingly functional visual
improvement over the spartan Ubuntu Classic or
Unity 2D interfaces in Ubuntu. It doesn't just look
slick, though; the dock allows customization for
behavior, appearance, plug-ins, and themes.
The OpenGL version of Cairo Dock is also known
as GLX-Dock, and the two share all plug-ins as
well as themes.
Both the dock itself and the app icons that sit on it
can have their own separate themes, and you
can add not just multiple docks, but sub-docks
for existing docks. More interestingly, you can
add applets alongside apps, which is something
the dock in OS X simply won't do.