Mark Wagner posted a useful script sample on his blog. The script allows you to browse through various objects on the DOM as well as JavaScript variables. I happened many times having the trouble to find those kind of information every time when I need them. So I think it is really a good one to have it in hand to save your valuable time.
See the full article here: http://blogs.crsw.com/mark/articles/652.aspx. And the sample starts below: