WowAce

Helps to track outgoing mails

Replacement for default bags.

Collects, analyzes and presents information about the virtual economy.

Tells you who bought your auctions.

Saves Auction House search queries.

Sneakily inspect how much gold your mouseover target has made so far.

GemCensus inspects people and records which gems they have socketed. Then displays which gems are the most popular.

Keeps track of gold and cash flow across multiple characters

Eliminates the spam from the chatframe and sums it up in a broker plugin.

Adds item values to chat messages.

Track any items you want in a tooltip

Manages the scanning of the auction house in a reliable an efficient manner.

An auction house AddOn to make the life of each fence easier.

Captures chatframe Tradeskill Links for later reference in an easy to read format

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

Repairs your items automatically upon visiting a vendor.

Helps to find other player's alts.

Tracks Black Market Auction House auctions.

An addon that automatically loots items for you.

User-configurable protection for your inventory. Automatically buys back mistakenly sold items.