Instant Source opens the additional toolbar at the bottom of IE window. It shows HTML of the current page, selection, or an item under the cursor. Also shows and lets you to save all external files on a page - Flash movies, style sheets (*.CSS), scripts (*.JS and *.VBS) and images. It has a built-in HTML viewer and editor with handy HTML, Javasript and VBScript syntax highlighting. Validates website HTML. All features are working inside IE.