WowAce

RuinBossTactics

Very very simple tooltip

OneBank

Keeps track of your reagents.

FuBar_Usage

Bits

Warn players about a specific aura (buff/debuff) at a specific stack via whispers and icons.

Assistace for Blackhand (Mortar warning in P2, custom says for bombs and marks in P3)

Mirror

Mail plugin for any DataBroker display.

xcRaid

Adds the ability to send mass mails to guild ranks.

Shows what stat was reforged in item tooltips.

Minimalistic LDB plugin that allows tracking of raid IDs across characters.

Shared handling of media data (fonts, sounds, textures, ...) between addons.

Adds spell-based range checking to Grid, and the ability to check multiple ranges.

Displays the remaining time on grid icon's cooldown animation.

A bar for all diminishing returns. Maybe nice for Arena, but intended for the third boss of Trial of the Crusader

Reduce the chance that talent switch be forbidden.

GigaItemAuction