WowAce

Library to help with querying unit talents.

TMrecruit

Display who crossed the charges on Thaddius

Shows optimal target to use various area healing spells

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

Cartographer_Noteshare

TGuildFrame

eePanels2

BossList

Library for tracking cooldowns of other players

Holy Power, Shadow Orbs, Rogue Combo Points and Monk Chi.

Stitch-1.1

opens/closes all bags when at merchant (instead of only the backpack)

Customize the appearance of the chat bubbles.

Automatic ammo reloading and selection, with warnings.

Shows current/dot cast haste values

RS_ClassColors

Bag and item management utilities

For Developers (of Addons which uses LibWho-2.0): show queues and queries in realtime

GridAlert