Here are the instructions (thanks to Renan from AWS) I received May 2015.
Launch a new, or use an existing, Ubuntu instance. I used Ubuntu 13.10 Saucy Salamander, 64-bit.10:08:04 AM
Update the system package list:10:08:04 AM
sudo apt-get update10:08:04 AM
Optional - I recommend upgrading all installed packages, even the kernel. There may be reasons not to want this, however:10:08:04 AM
sudo apt-get dist-upgrade10:08:04 AM
Install LXDE and TightVNC (This will take a while, depending on the instance type):10:08:04 AM
sudo apt-get install lxde tightvncserver10:08:04 AM
Reboot the system:10:08:04 AM
sudo reboot10:08:04 AM
Start up a VNC server (on localhost - since VNC itself isn't very secure, we'll use SSH)10:08:04 AM
vncserver -geometry 1024x768 -depth 16 -localhost :110:08:04 AM
Note: the VNC server will ask you to set and confirm a password. You will use this when you connect your VNC client.10:08:04 AM
Install a suitable VNC viewer, such as TightVNC on Windows: http://www.tightvnc.com/download.php 10:08:04 AM
or Remmina on Linux (usually installed by default, or at least available in the repositories).10:08:04 AM
Sorry, I'm not sure what Mac users install for VNC, but apparently there's a Java-based viewer at least: http://www.tightvnc.com/faq.php#macosx 10:08:04 AM
Create an SSH tunnel:10:08:04 AM
ssh -L 5901:localhost:5901 -N -f -i ubuntu@10:08:04 AM
On Windows PuTTY, enter the usual settings (login, address, key file) then go to Connection > SSH > Tunnels and enter 5901 for Source Port and localhost:5901 for Destination, then click Add, and start your session.10:08:04 AM
Finally, launch your VNC viewer and connect to localhost:5901, then enter the VNC password you chose earlier.10:08:04 AM