I got chance to attend Dallas ASP.NET UG and came to know about IE Developer tool.It is great a great tool for debugging and troubleshooting.Specially when you work with highly scalable and high customer facing site.Here is few useful inks for this .

Internet Explorer Developer Toolbar Download Load Link
http://www.microsoft.com/DOWNLOADS/details.aspx?familyid=E59C3964-672D-4511-BB3E-2D5E1DB91038&displaylang=en

IE BLOG
http://blogs.msdn.com/ie/archive/2007/01/09/ie-developer-toolbar-beta-3-now-available.aspx

Developer Tools Menu Bar Shortcut Keys
http://msdn.microsoft.com/en-us/library/cc848896(VS.85).aspx

Internet Explorer 8 Developer Tools GUI Reference
http://msdn.microsoft.com/en-us/library/cc848893(VS.85).aspx


Thanks,

Suresh Behera