HTTP Debugger

From SoftX:

Capture, analyze and debug all HTTP communications between the web browser on the client side and the web server on the other side. Internet software developers can use the HTTP Debugger to analyze the communication between their programs and the Internet.

Each HTTP transaction can be examined to see the HTTP header parameter values, cookies, query strings and error codes etc. All captured network traffic can be saved either in a RAW network format or in a decoded (how browsers see it) format.

HTTP Debugger works with all today's alternative browsers and their plugins, as well as with your own software. You can even monitor and debug ICQ, MSN, Yahoo Messenger and other popular Internet programs.