WowAce

Keeps track of current money and all your characters on one realm.

OneBag

Highly-configurable shield / absorb tracker.

Show what quests have changed

Tooltip of awesomeness. Moo. It'll graze your pasture.

Mutes various chat related annoyances while in capital cities and instances.

Reports in raid chat whenever a raid member "fails." /EnsidiaFails to configure.

CandyBar style cooldown display

Priority 3 loot announce addon

Addon to switch all your AceDB profiles via slash command. This tool also allows you to emulate profiles for non AceDB addons.

Food/water macro generator

Add-on that allows you to setup and quickly switch between different profiles of your action bars

Adds unreal tournament style sounds to PvP encounters.

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

DaHud

Adds your name to chat messages

Interacts with TinyTip modules, either integrated or standalone, to provide extra centralized functionality. Required for an ...

Shows mana usage as a percentage in a spells tooltip.

Keeps track of your current location.

Adds party/raid role icons in useful places