WowAce

Display bag usage on each of your bag slots.

TradeStop

Enables user defined sounds for Party, Guild, Raid and Custom Channel chat messages.

Mutt (Macro Update Target Tool) provides slash-commands that can patch the predefined targets in your macros.

Tracks profession specific cooldowns and items across all your characters

LDB data source displaying rested XP for whole account

Estimated time until current target will die.

AceBuffGroups

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

In-game EPGP guild helper, supports standby, main/alt shared pools, minEP, offpecGP. Fixed price list with progress multiplier.

Auto roll greed, need, pass or manually roll on items.

Library handling communcation for Magic* addons

Simple display and management of Away / AFK / Busy / DND status via broker or minimap

Transcendence Monitor for Monks

Litmus

HunterAEP

A jukebox for playing wow embedded music.

Broker plugin to display player orientation

Gives detailed descriptions of particular localities, as zones or instances, and provides optional TomTom integration.

Alternate Rune Display