WowAce

Notepad for Lua scripts and mini-addons.

Intelligent, slim paladin blessing management

Tattles to your default chat frame who has used their taunt nearby

What actual item level is an item? Yes, it's horrible we need a library for this.

Managing and viewing loot-type rolls

Shows the source of an item as a tooltip

GnomeCruncher

Tacticial pet battle information so you can be a Pokemon master

ClassButtons

Adds PvP status to Grid frames.

CallToArms

Simple addon that sends EG gear/main data without running the full client

A DPS Data Broker plugin.

FriendlyArrow

Exports encounter journal data into XML

Track friends / enemies in a convienent window, with optional logging

Metrognome

allows you to flip cards of omens by spinning your mouse wheel; counts cards opened and money earned per session and lifetime

World of Warcraft Textmate Bundle

EatTheFeast