WowAce

Lists and/or reminds people missing flasks or food buffs at every ready check.

Provides training reminders to help decipher the Blizzard Spell Alerts.

Displays events from Calendar for upcoming week in tooltip.

A raid buff tracker

Enhances the StackSplitFrame with numbered Buttons, a '1-Click Mode' and a 'Auto Split Mode'.

Flames anyone who lets his debuff expire on Malygos Phase 3

FuBar_SpeedFu

Tool for easy task assignments in raids.

SkadaScroll is a plug-in for Skada Damage Meter that provides additional options for scrolling the bar displays. It requires ...

Replacement for WoW's flash/fade functions.

EnvenomX

Display combo points for Arcane Blast debuffs

Social tracking suite.

Adds pipes which can control arbitary other statuses (like toggle status on key or "in combat"-state).

Adds unreal tournament style sounds to PvP encounters.

Expiration

An herb and ore gathering add-on with a focus on ease-of-use.

Helps to track outgoing mails

Shows a money overview for your current realm in the tooltip on the money in your bags

Bars showing amount of buffstacks