Mozilla. For all the shit it catches in the press, I am amazed at how stable and useful it is. I have been grabbing the nightly builds for some time now, but since I have been home on my dad’s machine, I have been using it exclusively (because my dad doesn’t want NS installed; he is an IE weenie now).
Anyway, it rarely crashes on me (remember, it isn’t even beta yet), and it screams. I can’t wait until this is rock solid.