While this is a very basic piece of code it adds a very nice effect to any item you choose. The MooTools Fader Class will fade any item to a specified opacity and fade it back to a specified opacity.
Parameters and Options
elements: Parameter. This is a CSS selector that will be used to select your items.
fadeTo: Option. This is the decimal value that your item will be faded to. E.G. 0.3
fadeFrom: Option. This is the decimal value that your item will be faded back to. E.G. 1
duration: Option. The speed of the animation in milliseconds. E.G. 250
transition: Option. The transition of the animation. E.G. Fx.Transitions.Sine.easeOut