WowAce

Sets you to DND when you fight a boss, and some other crap.

MeleeFrame

Adds an additional spell alert if you have more than one charge of a buff that is normally tracked by the in game spell alert...

AllYouCanEat shows information about the following statistics: beverages, foods, bandage types, potions, elixirs and flasks.

Allows for gold tracking across multiple time frames

Adds Blizzard, oRA2, oRA3, CT_RA MainTank or Dungeon Finder Tank icon (shield or MT, 1, 2 ... 10) or text (MT or MT1, MT2 ......

Raid assignments planner

Keeps an eye on someone's distance from you, and alerts you if they get too far.

Keeps tracks of /rolls.

Shows all the targets in the raid

TEALib

Automatically switches Profiles of addons when changing spec

MD5Lib

Raid Inviter

CatPoints

CraftBotFu

Calculates the relative value of attributes towards physical dps.

Reputation tweaking module for TweakHub with auto watched faction selection and detailed rep info updates.

A simple addon that warns you if your pet isn't attacking while you're in combat.

A Latency Data Broker plugin.