Addon that lets you know when things proc.....

I you can remember from cataclysm, whenever mages would get an instant fireball cast, or when priests got an instant mind blast, there would be a nice looking and subtle indicator on your screen letting you know. I'm looking for an addon that does just that, sometimes it's hard to see the green <Fireball!> Text when you have a bunch of heals on you.

Powerauras

Try Cheese or Mage Nuggets for ready-to-go addons, but also customizable.
Try PowerAuras, Weakauras2, NeedtoKnow, TellMeWhen for addons that offer more features but need to be set up.