I assume we all need to get this for buffs and what not.
So here a link: http://wowaddons.snowolf.eu/index.php?act=view&id=30
For those who don't know what it is, the leader assigns buffs that you will responsible for each class. All you have to do is click the button and bam job is done. It keeps track of who's doing what in just a little frame, so if you forget what you're doing just check back there and you won't look stupid asking what your assignment was. :D