WowAce

Provides the ability to suppress specific spellcasts like "Deaden" from your casting bars.

For Developers (of Addons which uses LibWho-2.0): show queues and queries in realtime

Shows a nice Soulstone Monitor.

adds navigation buttons to Encounter Journal

Keeps track of durability and pops up a dialog to repair when you go to a vendor who can.

fmBuffCheck

Privacy2

Reminds you if your flask/elixir and/or Augmentation Rune and/orfood buff is about to expire or has expired

NabuFiveSec

Adds on-screen buttons for the farming tools and seeds.

Enables the filtering of items when you visit a vendor

Displays classes and specialisation dependent stat priorities provided by icy-veins.com

Rep2 displays a message, which shows how much reputation you gained, and how much is needed until the next standing.

Nudge

Shared handling of media data (fonts, sounds, textures, ...) between addons.

A full package of auras for all 3 Shaman specializations

ColaLight

Prompts for canceling of pet battles if no rare pet is found in the opposing team.

Fires events whenever a raid member "fails".

Track any items you want in a tooltip