http://blogs.msdn.com/ie/archive/2005/09/06/461675.aspx
- Remove all non-text elements from the current page
- Look up the currently selected text in the dictionary or encyclopedia
- View the source of the currently selected HTML elements
- Copy any image from the page
Since they’re just DHTML, you can view (and tweak!) the DHTML source of the IEToys by looking inside the installation folder.