Situation: I have to remote support a lot of different users at different companies, not a problem when they're in their offices, I VPN in then use VNC in a pretty standard way. The difficulty arises when they are out on the road, at home or somewhere with an internet connection but no vpn setup

1. Assuming you have VNC installed you should find a Start Menu option to run the VNC Viewer in Listen mode.
2. If you are behind a firewall you need to add a new port to the address translation (this foxed me for a while, the listening viewer uses TCP port 5500, not the usual 5900).
3. The client should have the VNC Server running, tell them to right-click on the icon and select "Add New Client".
4. It will prompt them for an address, obviously your IP or Dyn-DNS name.
5. After a moment a viewer session should launch on your desktop.

The nice thing about doing it this way is the connection originates from the client, which most firewalls will accept quite happily so you don't have to explain it to non-IT people. I'm assuming if you need to do this you know enough to reconfigure your own firewall.

This needs VNC server running at client end. And a listening viewer on your side. The server on the clients end then connects through to your listening viewer by right clicking on the server tray icon and clicking “add client”. Once this is done a Window will pop up at your end with the VNC session contained in it.

** As an update to this post you should really use TightVNC as it is alot quicker than normal VNC.