I use Firebug and the Mozilla JS console heavily, but every now and then I run into an IE-only JavaScript bug, which is really hard to locate (ex: error on line 724, when the source HTML only has 200 lines).
I would love to have a lightweight JS tool (a la firebug) for Internet Explorer, something I can install in seconds on a client’s PC if I run into an error and then uninstall. Some Microsoft tools take some serious download and configuration time.
Any ideas?
You might find Firebug Lite useful for that.
Its bookmarklet should be especially useful when debugging on a user’s machine.