XUL Base

Some real-world examples of XUL

* SimoHealth Software - Organize medical expenses and medical histories.

* World of warcraft (7 million users)

* Nokia Media terminals

* Wengo VoIP client

* Topstyle Css editor

* AOL browser

* Le Monde Newspaper (Backend application)

* wysiwyg HTML editor Nvu for Linspire Inc

* ActiveState Komodo Professional integrated development environment (IDE) for dynamic languages.

* @Mail (AtMail)

* Google Adwords Editor

* Thunderbird

* Open iTunes!

More examples here