WowAce

Add a more noticeable "ping" to the fishing bobber sound

Kollektiv Unit Frames

CombatFilter

Enables you to save multiple talent configurations

SimpleDrumAnnounce

Tracks Prayer of Mending

Save, load key bindings, set autoload for specchange, etc

Adds spell-based range checking to Grid, and the ability to check multiple ranges.

Tells your party members when you interrupt stuff, or fail to do so.

Closes chat when the player is instead trying to move

BlessingBar

Adds useful slashcommands for mounting, and more

Broker launcher plugin for Blizzard Equipment Set

Tracksw

With Mists of Pandaria Blizzard publish all characters from an account unless you disable that 'feature'. This addon warns you.

Tracks money/tokens across all your characters; /goldwatch for options.

BigWigs_ThaddiusArrows

AIBot

Spew

Reports into chat the status of your lockouts.