WowAce

Sneakily inspect how much gold your mouseover target has made so far.

Monitors for friendly deaths and announces them as in Myth: The Fallen Lords

Notifies you of experience gains

Libary for cleanly inspecting other players

Facilitate better communication for loot councils

Adds an Atlas button to FuBar.

Displays info about who rolled Need/Greed/Pass on items that are currently rolled for

Battleground Timers in a HUD around the Blizzard BG status

Swiss Army knife for instances, including player tracking, ignore buttons, loot tracking, notes, and more.

GemCensus inspects people and records which gems they have socketed. Then displays which gems are the most popular.

Fade Blizzard Raid Frames

SacredBuff

Automatic ammo reloading and selection, with warnings.

Puts a timer in /yell when you get Unbound Plague during the Heroic Professor Putricide encounter

Show a rough range indicator

Fires events whenever a raid member "fails".

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

MountUp

Display an arrow that points to a raid/party member anchored to raid frames

Loudmouth