WowAce

Modular and lightweight party/raid frames.

Better quest log and tracker

Automagical macros for each talent tier.

FuBar_InnboundFu

FuBar_PTReagentFu

Keeps track of durability and pops up a dialog to repair when you go to a vendor who can.

Check the quality of wild battle pets

Reno is a slash-command that can patch predefined options in a macro to change which abilities will be chosen.

Personal buff monitor - are you buff enough?

Sphere

Adds achievement reminders to BigWigs

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

Keeps track of space left in your bags.

Shows you the radius of your totems.

Combination of Titan LootType and Roll - stripped down and cleaned up.

WhoDrop

Helps you automate selling stuff

Smart mount randomization on a button! Empty coconut halves not included.

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

Display an informational fighter jet style HUD while flying or riding