WowAce

Announces interrupts in the chat

SurgeonGeneral

Tools for MultiBoxers or Group questing/leveling

Klappa

Add-on that shows in a unit tooltip window a number of killed mobs of the same kind

Hemlock

This will keep track of how much you have paid per item in your inventory. Only one of (Auctionator, Auctioneer, AuctionLite,...

Automatically sells low quality gray items and selected white items to the vendor.

CombatLog in SimpleCombatlog style

Simple library that handles multiple levels of logging.

Guilder brings common guild-raid tasks together in one convenient place.

Keeps track of durability and pops up a dialog to repair when you go to a vendor who can.

An auction house AddOn to make the life of each fence easier.

Fixes strata bugs in UI windows

Manufac

MainAssist

Fubar_ChannelWatchFu remade for Broker

IncomingHealsLib

Simplifies GDKP bidding processes

Allows customisation of login/logout system messages.