I am looking for an addon, that alerts when like, Hamstring is running out on the target, it shows some text in the middle of screen, something like "Hamstring is going out!" , "Rend is going out!" , "Piercing Howl is going out!". If you know what I mean.
Also have a look at PowerAuras ... it's essentially a buff/debuff watcher for yourself, your target, your focus, etc. You can set it up to flash text, flash graphics, icons, etc. You can animate them, or just display them - pretty much anything you want.