WowAce

Spawns toasts for looted items, money, and currencies.

Paints your known blueprints red.

Lightweight time display, with micro menu and memory usage tooltip.

BarAnnounce3

One-click smart mounting.

Interface-central mount management

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BiGOpt

Library to help with querying unit talents.

Draws 3D portraits for main units that can be moved or resized at will.

SwapMagic

Heal and decurse by clicking on customizable raid/party unit frames

A simple range indicator for optimizing Halo damage.

Makes grid QuickHealth aware

SmartQueue

Helps you decide which ability to use next according to priority you set

RaidInfo

Cartographer_Stats

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

DotDotDot