WowAce

Save and send chat messages to many channels. Allows quick item and profession linking within your messages.

Test whether the player can really dispell a buff or debuff, given its talents.

Automatically invites player from templates.

On login, displays changes to your guild since the last time you logged in.

Keep your pet fed

Library providing mouse-click support for LibQTip-1.0.

DHUD2

Cryolysis

A library to help with localization of Archaeology artifacts

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

Adds Buff/Debuff icons to the grid frame.

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

Disease Tracker for Death Knights.

ezIcons

FuBar_AbramsFu

Leveling guides for trade skill professions.

xchar

FuBar_switcherFu

SanityBags

FuBar_PetFu