<p>I'm currently experiencing an intermediate problem with some inherited client side javascript. Every so often the users' experience a browser hang with the cursor becoming an egg timer and then the browser failing to respond. </p>

<p>I'm having real difficulty in determining where the issue is arising from. Short of disabling large chunks of javascript at a time is there any way to detect a hang in internet explorer and then examine the stack trace to determine the last few functions called in order to localise the problem?</p>

<p>Any help with this would be really appreciated. </p>

Update
: You can use
Web Development Helper
or
IE Dev Toolbar
to trace your Javascript calls.
Fiddler
is also a powerful web debugging proxy.
If you want to eliminate the IE part of the problem, disable all unnecessary addons loaded in Internet Explorer first. I had a big problem with skype addons.
If you want to do low level monitoring, you have to use tools like Process Explorer and Process Monitor. They have functionalities to show the stack trace, your trace of files and registries being accessed etc from your IE.
For javascript profiling, you can use a tool like
firebug
.