Headless Skype

Install Xvfb, X11vnc, screen and some required libraries, download Skype, install it, then start it in a virtual X server on display 0:

apt-get install xvfb x11vnc screen ia32-libs-gtk
wget -O skype-ubuntu-intrepid_2.1.0.81-1_amd64.deb "http://www.skype.com/go/getskype-linux-beta-ubuntu-64"
dpkg -i skype-ubuntu-intrepid_2.1.0.81-1_amd64.deb
screen -S Skype xvfb-run -n 0 -s "-screen 0 800x600x16" /usr/bin/skype

Attach a VNC server to the virtual X server on display 0:

x11vnc -display :0

Use VNC client like UltraVNC to connect to the VNC server.

You're wondering why anybody would want to do that? Here's why: Skype over Asterisk