WowAce

Violation

Database of Diminishing return categories and general data

Configurable Castbars

Adirelle's unit frames, based on haste's oUF.

Automated smart raid marking to speed up trash clearing in instance runs

An extension to the default WoW Unit Frames.

Quest History tracker and shows lists of quests in each category

Show buffs on nameplates.

Antagonist

Keeps track of your current location.

Tracks the HoTs you cast.

Database of item upgrade IDs

Keeps track of your top hits, heals, criticals, etc.

Adds a status to Grid for debuffs applied by Raid Bosses.

Queing of /who and SendWho() queries and a much better interface (see docs), with gurantee to be executed & callback.

Configure triggers to send messages to your raid team such as timers, rotations, and health/power based triggers. Raid smarter not harder.

Entertaining kill-shot notification.

Adds various information based on PeriodicTable to item tooltips.

Textures for Stop Motion

Switch macro depending on zones or BigWigs boss modules.