The ChameleonNavigator is a standalone application that uses the IE engine to test the web content depended on user settings (browser name, accepted languages and referrer)
Websites can show different content when viewed with a certain UserAgent.
On the remote server the application will be identified as Netscape, Opera, Firefox, Google bot or anything else you define in "UserAgent" field.
If the server sends different responses, you will see it. On the task bar at the bottom of your window is an size indicator, that shows the source length.
Also you can easy check server's response content depended on user language or referrer.
By default, the program has different profiles (eg. Windows IE6, Linux Firefox, Mac Safari etc.).
However, you can always change these or add more.