Firefox nighty is the new version of Firefox, it’s in beta, http://nightly.mozilla.org/. Has anybody used it. It’s very promising in the responsive front of web design, particularly in using the development view. http://www.youtube.com/watch?v=n-9Q7xoC51g
Apart from this, another cool way to test your responsive websites is with this candy Chrome plug-in, http://ripple.tinyhippos.com/.
I just wanted to share this, and if anybody had any other cool ways to test their websites for the mobile world!