Check out these interesting articles by chrishayuk:
I’ve found this solution implemented with AJAX: “You can remote your PC anywhere without pre-installing any client. As it is purely HTTP, you can VNC even behind firewall or proxy. Java VNC server able to run on Windows/Mac/Linux.”
Chris Knowlton has published on his blog an interesting comparison between these two methodologies.
Click here to read the article.
Other interesting resources are:
Click here to read an article explaining the configuration of a Fedora 8 Server using LAMP, Email, DNS, FTP, ISPConfig.
If you use other distributions take a look here:
Just use a published PAC (Proxy Auto Configuration) script and WPAD (Web Proxy Auto Discovery) protocol.
Click here to read the instructions by Jonathan de Boyne Bollard.
An article about this subject can be found in the Scott Lowe’s weblog.
Here are some useful guides to help configure VPN software clients using TheGreenBow IPSec VPN Client.
I’ve found this document on the Zyxel site for configuring Zywall VPNs.