Xnest

From Superk

Xnest runs a seperate X session as a child process of the parent X session (the desktop environment you are working in). This is a fantastic way of messing with desktop environment configs or another desktop environment (ie, Gnome within Fluxbox) without having to exit out of the parent X session.

Get the Xnest package (easy with the Debian Xnest package)...

$ sudo apt-get install xnest

Run a new X session...

$ Xnest -ac :2 &

Export the new display environment variable...

$ export DISPLAY=:2.0

Start up your desktop environment of choice...

$ fluxbox &

There you have it! You're running fluxbox (in this example) within your existing X session!