WowAce

A boss encounter engine used by other add-ons

QuestAnnouncer

FuBar_RegenFu

Displays bars depending on your professions

ClosetGnome_Fishing

Fail display for Recount based on EnsidiaFails filtering options

Add TomTom Waypoints for Flight Masters in classic

GratuityLib

tekSupport

Provides the ability to suppress specific spellcasts like "Deaden" from your casting bars.

BalerocHealers

Considers an item against all the items you have to determine whether or not it is an upgrade

FuBar_FuzzyClockFu

BuffProtectorGnome

Provides more visible access to dungeon and raid difficulty settings via FuBar.

FuBar_ChatLockFu

Adds four icon indicators to Grid (top, bottom, left and right).

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

Shows the price of a single item in the Auction House.

Merchant, gossip and taxi tweaking module for TweakHub.