WowAce

Compact scrolling vendor frame

See all incoming casts on your target. Also includes resurrection monitor. Uses libhealcomm-3.0 and librescomm-1.0

Notifies you of new calendar event invites and reminds of upcoming events on all characters and realms

Surfaces

pMutilate

Shows a countdown bar for the duration of auras (e.g. HoTs, DoTs)

Simple DataBroker plugin to display current GuildLevel, current GuildXP, max GuildXP & percentage actually earned of daily ca...

Makes it very easy to collect rare battle pets.

Mute error messages of N next spell cast.

Write event handlers in a simple GUI in-game

PoisonSwapper automatically manages weapon swapping for maximum DPS

Adds Debuff Highlighting to oUF.

ControlFreak

Baggins_ItemRack

Automatically restock items from vendors and your bank

Opens professions and shows their skill level.

SupplyAndDemand

Add TomTom Waypoints for Flight Masters in classic

Adds cooldown timers to your trinket procs

Tracks spiritual innervation on Garajal