Cool IE Tools
If you do web development you may find these tools invaluable:
Toggle Borders
The accepted way to debug complex table-based HTML pages is to add a border="1" attribute to the <TABLE> element. Toggle Borders is a utility which automates this and more. It is accessed from the context menu in Internet Explorer and will color-code tables, spans and divs for you to see how your website, or a third party website has been layed out. Select Toggle Borders again and the color-coding is removed.
Full Source
Full Source is an Internet Explorer menu extension which displays the source Internet Explorer is displaying, directly from the Internet Explorer object model. This is useful wherever javascript is dynamically writing HTML into the DOM, or where XSLT has been used to generate HTML.
I use both of these tools, and while they aren't something you use every day, when you need them they come in very handy.