MooTools has been around for quite some time now. And there are tons of nifty things you can do with it as well as tons of things other people have done with it that are free for download. If you take a look at the home page of the Apt 3 Studios website there are a few MooTools things happening. So lets Moo it up for a bit 
First is the drop down navigation. The smooth animated drop down is all MooTools. It is a highly modified version of UvumiTools. It gives you all the basic framework of a dropdown menu, all you have to do is do some customization of it with graphics and how you want it displayed.
Second is the content slider at the top of the page. This really cool content and image slider is a highly customized version of Slide it Moo. This gives you everything you need to creat simple and complex slide animations with tons of expandability.
Now here is one issue that you have to watch out for with the MooTools javascript library. That home page also uses some jQuery operations on it as well, and unless you setup your scripting correctly MooTools and jQuery will not play nice together. So to make the two javascript libraries friends you have to wrap all your jQuery javascript code within the jQuery.noConflict(); option as well as renaming the standard ($) object name that jQuery and MooTools are both trying to modify.
You see in order to work, jQuery and MooTools creates an object (in this case ‘$’ is usually what most of the scripts use) and then it uses its javascript functions to then modify that object while the code is running. So when MooTools creates the ‘$’ object, jQuery wants to overwrite the ‘$’ in the running memory. The way around this is to rename the standard object and call to that object throughout the ENTIRE code for one of the scripts and then wrap that code in the jQuery.noConflict function. That way each javascript library has its own object to play with and instead of teaching the two to learn how to share, they each get their own shiny new object.
Now you can utilize functions of two libraries instead of one. Keep in mind this method is more resource intensive and it is always better to just use one library instead of two. However, its nice to be able to use both if you really want to make a web page ‘pop’.
