Extend MooTools' fade in & out.

mootools-fade.js

/**
 * Code snipet for fade in & out with MooTools.
 * @author Takahashi Fumiki
 * @description 
 */

Element.prototype.fadeIn = function(display){
	if(display == undefined)
		display = "block";
	var fx = new Fx.Morph(this);
	this.setStyles({
		visibility: "visible",
		display: display,
		opacity: 0
	});
	this.fade("in");
};

Element.prototype.fadeOut = function(){
	var fx = new Fx.Morph(this);
	fx.start({
		opacity: [1,0]
	}).chain(function(){
		this.start({
			display: "none"
		});
	});
};