Email Parser and Username Generation - Burp Suite Extension
Burp Suite allows for extensions to be created in Python. This is a Python extension that will parse email addresses out of selected URLs from the target tab and display them in the output window of the Extensions tab. It will also generate a list of usernames from the emails found with basic permutations.
Demo / More Information
Download the latest version of jython and configure Burp to use under Extender->Options->Python Environment.
Add the Python script under Extender->Extensions. During loading there is an output window that will inform you of any errors.
From the Target tab, select any URLs that you have visited, right-click and select "Get Emails" or "Generate Usernames" from the context menu.