WowAce

Reduces interface tedium by doing the little things for you.

Give logical progression of Mining, Herbalism & Skinning. Will not be updated with WoD zones

Adds manabars to the sides of Grid frames.

Simple library that handles multiple levels of logging.

Library providing mouse-click support for LibQTip-1.0.

Searches bags/banks of all your characters/guilds.

Allows tradeskill usage by clicking items or reagents.

Set the clicking action for Grid buttons

Tracks interrupts

GemCensus inspects people and records which gems they have socketed. Then displays which gems are the most popular.

Tools for MultiBoxers or Group questing/leveling

LilSparky's Workshop mod for Trade Skills

Pins on the World Map for quests you have not completed yet

Reports in raid chat whenever a raid member "fails." /EnsidiaFails to configure.

ItemBonusLib

Adds a button to your character and inspect window that shows a summary of gear enchants and gems.

Good old LibTourist-3.0 for WoW Classic Era

Displays classes and specialisation dependent stat priorities provided by icy-veins.com

Raid Frames using the oUF framework.

SpyGnome