function after(){
                o.useDisplay ? fly(dom).setDisplayed(FALSE) : fly(dom).hide();   
                fly(dom).clearOpacity();
                fly(dom).setPositioning(r.pos);
                st.width = r.width;
                st.height = r.height;
                fly(dom).afterFx(o);
            }
Slides the element while fading it out of view.  An anchor point can be optionally passed to set the 
ending point of the effect.
Usage:
<pre><code>
// default: slide the element downward while fading out
el.ghost();

// custom: slide the element out to the right with a 2-second duration
el.ghost('r', { duration: 2 });

// common config options shown with default values
el.ghost('b', {
    easing: 'easeOut',
    duration: .5,
    remove: false,
    useDisplay: false
});
</code></pre>
@param {String} anchor (optional) One of the valid Fx anchor positions (defaults to bottom: 'b')
@param {Object} options (optional) Object literal with any of the Fx config options
@return {Ext.Element} The Element