WowAce

Melee stats Data Broker plugin.

PricePer

LibRockDB-1.0

A data broker plugin showing your longest fight and your current fight time.

Keeps an eye on someone's distance from you, and alerts you if they get too far.

MaxStats

oUF element for highlighting debuffs that are dispellable by the player

Aggro Warning System for Parties and Raids.

Automatically converts a party to a raid when you attempt to zone into a raid zone without a raid.

Keeps track of important de-/buffs in a splash screen

KivinLootzor

See all incoming casts on your target. Also includes resurrection monitor. Uses libhealcomm-3.0 and librescomm-1.0

oUF_HolySmurf

Shows an arrow to your bite victim during the Blood-Queen Lana'thel encounter in Icecrown Citadel (your raid leader must be r...

A simple, zero config, trash item seller

A variant of AceGUI's Frame container with an editable input field

Social tracking suite.

Hides MicroButton Alerts

CompostLib

Opens professions and shows their skill level.