WowAce

Better quest log and tracker

Lightweight time/date display with optional hourly chime.

Tracks the precise arrival & departure schedules of boats and Zeppelins around Azeroth and displays them on the Mini-Map and ...

Keeps track of gold and cash flow across multiple characters

StatStain

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

Add a line to herb tooltips that shows what pigment they produce.

Simple display and management of Away / AFK / Busy / DND status via broker or minimap

CCBreaker

Shows skills in a tooltip and allow them to be used. Also keeps track of Cooldowns.

RBM

FuBar_ShardCountFu

Acolyte2

Reno is a slash-command that can patch predefined options in a macro to change which abilities will be chosen.

Building a Better Mailbox

Assister

Death reports

Display the global cooldown around your cursor. (+ other stuff)

item2phpBB

AceBuffGroups