Do you need a good debugger for Internet Explorer?

I often felt the lack of a good debugger for Internet Explorer during my web programming...

For Mozilla Firefox there's a wonderful FREE add-on called Firebug , and I really miss something like that for Internet Explorer.

I tried using MS Script Debugger and also MS Script Editor, but I don't like them.

Then I found a nice blog post that help me a lot during my web programming:
How to debug JavaScript with Visual Web Developer Express

Reading the comments to that post I also found this nice screencast that visually explains how to accomplish the set up of the free Microsoft web debugger.

Enjoy! ;-)

P.S.
Is there any other good (free) debugger for IE? Let me know.