Pratap Ladhani

I came to know of a nice tool today, while reading about AJAX.NET Professional at Michael Schwarz's site, by the name Microsoft Fiddler.

What is Fiddler?

Fiddler is a HTTP Debugging Proxy which logs all HTTP traffic between your
computer and the Internet. Fiddler allows you to inspect all HTTP Traffic, set
breakpoints, and "fiddle" with incoming or outgoing data. Fiddler is designed to
be much simpler than using NetMon or Achilles, and includes a simple but
powerful JScript.NET event-based scripting subsystem.

Read more about Fiddler at these MSDN Articles - Fiddler PowerToy - Part 1: HTTP Debugging and Fiddler PowerToy - Part 2: HTTP Performance.

Happy Fiddling :)