WowAce

Quest History tracker and shows lists of quests in each category

Adds a status to Grid for debuffs applied by Raid Bosses.

Provides access to all Portal and Teleport spells on right click of one button.

Smooth combat HUD based on ArcHUD2

mount and companion manager

Point to quest POIs on your minimap

Tooltip of awesomeness. Moo. It'll graze your pasture.

Keeps account of attendance and loot for raids, parties, bgs, arenas and solo for questing.

Tracks the HoTs you cast.

Library providing mappings between trade skill recipes, spells and created items

Textures for Stop Motion

Collects Herbs, Mines, Gas Clouds and Fishing locations and adds them to the worldmap and minimap

Marks the locations of Hallow's End candy buckets on the worldmap and minimap.

Queing of /who and SendWho() queries and a much better interface (see docs), with gurantee to be executed & callback.

Good old LibTourist-3.0 for WoW Classic Mists of Pandaria

Adirelle's unit frames, based on haste's oUF.

Configurable Castbars

Create panels for customizing your UI, sucessor to eePanels

Shaman totem bar

Displays information about the current zone on the World Map, for WoW TBC Classic