WowAce

This will keep track of how much you have paid per item in your inventory. Only one of (Auctionator, Auctioneer, AuctionLite,...

FuBar_uGuild

LDB display of currencies, gold totals and session / daily / weekly statistics for all characters on a server.

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

Displays how many times you have jumped.

Simple quest item bar.

Check the quality of wild battle pets

Nihilum Raid Tracker, originally written for the EU guild Nihilum.

Fubar_ChannelWatchFu remade for Broker

Tracks SendAddonMessage Spam

Mapster's Minimap brother

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

Enhancer

pDebuffList

Dims action buttons.

Display bag usage on each of your bag slots.

Estimated time until current target will die.

Shows skills in a tooltip and allow them to be used. Also keeps track of Cooldowns.

Insanity resource tracker for shadow priests.

Tells you the Tiller, what food they like, and if you have fed them today for the quests A Dish for ...