WowAce

Quest History tracker and shows lists of quests in each category

Deus Vox Encounters

Death analysis tool

Collects Herbs, Mines, Gas Clouds and Fishing locations and adds them to the worldmap and minimap

Fires events whenever a raid member "fails."

Database of Vendor locations for HandyNotes

Bayi's Extended Questlog

Unit Frames of awesomeness. Woof. It'll bite your face off.

Shows you a much bigger icon selection frame

Compact rune and proc display for Death Knights.

Calculates optimal reforging for given weights/caps.

Additional information about player spells.

Database of Trainer locations for HandyNotes

Display front-end for LibGuildPositions-1.0 using HandyNotes

OneBank3 will combine all the bank bags into one frame.

Wowhead Data dump for GatherMate

Unit frame addon using Ace3.

Barks at you when you target a crowd-controlled unit

A library to provide mobIDs for bosses.

Dropdown library for Ace3 options, extensible to other options formats. Works ok.