Addon: Power Auras

This addon allows the user to create any type of graphical appearance due to a set of criteria. Want to know when that spirit trinket is ready? Want to know when you get a specific buff? Want to know when your dots are about to run off your target? Want to know when water shield runs out? Want to know how many charges are on lightning shield and when the best time to release them is? Want to know when you can purge/dispel/soothe? These are just a few examples, there are nearly endless applications for this mod. Nearly required.

http://wow.curse.com/downloads/wow-addons/details/powerauras-classic.aspx