Previously (like 5 minutes ago) I blogged about HTTPLook. That review was written a few months ago & copied over to my new blog (here).

So, recently I came across Fiddler, a free utility made by Microsoft (or an MS employee with some free time). It actually acts as an HTTP proxy that your browsers run through, and it displays all the HTTP calls in its main window as seen below:

Click for full image

One of the things I like about it is it's quite stable. We had problems with HTTPLook "corrupting" our network settings, requiring a reboot to fix. Fiddler runs cleanly, can save the traces to logs for later inspection, and has a host of other features that many people would never use. We usually use it for debugging missing HTML components (i.e. a javascript or image file might be missing from an HTML page, yet the error isn't visible by inspection), or debugging web service calls (i.e. from .NET winforms applications or Flash apps). But Fiddler also has an interesting guide to performance tuning using HTTP sniffers. Might be worth checking out.

So, if you need an HTTP sniffer on Windows and are cheap, check out Fiddler. You just might like it.