I recently stumbled across someone's (also here) invention of a word to describe those committed to Christian non-violence. Some say that the word "pacifist" sounds just too passive and rightfully so. Christian non-violence is in fact a non-violent resistence because of the kind of life we are called to live as follower's of Jesus ... anything BUT passive and non-active. And, shalom gets at the heart of what is really going on when Christians say they are non-violent. To live out God's shalom as we have received it in Jesus Christ is so much more than non-violence. That said, I am a Shalomite.
Also, for your interest and enjoyment, check Charlie's site for a recently stimulation converstation on Just War and Christian pacifism.