WowAce

Bars showing amount of buffstacks

SQL-driven database system for Lua

Shows at-a-glance what raid buffs/debuffs you have.

Adds your damage to Scrolling Combat Text

KC_PlayerFramePlus

Sneakily inspect how much gold your mouseover target has made so far.

Shows a countdown bar for the duration of auras (e.g. HoTs, DoTs)

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

Tells you which blob to kill at the Yor'sahj encounter in Dragon Soul.

Quickly builds /target macros for immediate use.

A library to provide tools for formatting money and time.

In-game EPGP guild helper, supports standby, main/alt shared pools, minEP, offpecGP. Fixed price list with progress multiplier.

Database of FlightMaster locations for HandyNotes

FuBar_SpeedFu

Drops the least valuable item in your bags to make space.

Shows where the equipment of inspected users or yourself is from.

WhiteboardNG

Adds 3 indicators to each side (top, bottom, left and right).

Surfaces

Prompts for canceling of pet battles if no rare pet is found in the opposing team.