WowAce

Allows you to create icons, which can be customized greatly by user's input. CiR is more than just the usual cooldown tracker.

Enhances the Equipment Manager to let you control the helm/cloak visibility for each set.

"Range finder/display for Discipline's Holy Nova"

Tracks Black Market Auction House auctions.

Combat Alert

Complete Replacement for Inventory and Bank Bags.

UnitActionBars2

CombatAnnounce

Mana Regeneration Information

Provides access to all teleporting spells and items on right click of minimap button.

Adds 3 corner indicators to each corner of the Grid frames.

A Raid DPS Data Broker plugin.

Combat log replacement

T_Tracking

Changes the quest log back to how it was before Patch 6.0.

Shows the group leader, raid assistants, and master looter in Grid.

Tracks and announces interrupts (eg. Hit/Miss/Immune) and is also able to track and report "wasted" interrupts (those which d...

DebuffEnough

Adds Raid Target Icon status to Grid (Player or Player Target).

Enables you to see Chinese, Japanese and other languages in game