JS file that can be downloaded here
includes these 3 functions:
originalInnerXHTML (element, includeElement) – returns original page source string content inside chosen element and including that element if includeElement is set to true
originalOuterXHTML(element) – returns original page source string content inside chosen element including that element
originalPageSource() – returns the complete original page source string
These functions were originally pubslihed on http://www.moyablog.com/2011/10/06/innerouter-xhtml-or-how-to-get-truly-original-source-of-element-in-javascript/