WowAce

Buffalo

Tracks the precise arrival & departure schedules of boats and Zeppelins around Azeroth and displays them on the Mini-Map and ...

A fork of BananaDKP.

A simplistic clock.

Monk Brewmaster/WindWalker Priority and Buff/Debuff Tracking Tool

Enables user defined sounds for Party, Guild, Raid and Custom Channel chat messages.

HunterAEP

Litmus

Auto roll greed, need, pass or manually roll on items.

Gives detailed descriptions of particular localities, as zones or instances, and provides optional TomTom integration.

Provides data about all artifacts in the player's possession.

FuBar_SWStats2Fu

A jukebox for playing wow embedded music.

Quixote

Keeps track of space left in your bags.

Tells you if you're buffed

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

Loudmouth

Building a Better Mailbox

WhiteboardNG