Firefox privacy, security and anti-tracking: a comprehensive user.js
Dot Browser for Android
A scriptable browser like PhantomJS, based on Firefox
BrowserBD is a Java based portable browser app for web browsing/IM
You can do more!
A fast and customizable web browser for Windows using Gecko.
Airfox is a free and fast web browser. It uses the Gecko Engine.
Web browser with the gecko rendering engine
A fast, customizable, and lightweight Web browser for Windows
Visual/CSS regression testing with PhantomJS