WowAce

FuBar_AbramsFu

Complain about crowd control breaks.

Instant PROC notification

DeclineDuel

FuBar_NetStatsFu

Saves contents of your guild bank and sends/receives updates over the addon channel

eePanels2

Displays info about who rolled Need/Greed/Pass on items that are currently rolled for

NRT_EPGP

RotLatency keeps track of your reaction to cooldown expiration.

Displays events from Calendar for upcoming week in tooltip.

A frame designed for each specialization of druid's watching their main power and important buffs/debuffs

For Developers (of Addons which uses LibWho-2.0): show queues and queries in realtime

Monitor the remaining duration on your Mysterious Eggs and other perishable items.

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

FuBar_BongosFu

Draws some lovely 3D portraits in the standard Blizzard artwork.

Hitman

Provides buttons and keybinds for raid flare world markers that never stop working mid-session

Client for MagicDKP which handles standby calls and bidding on items.