WowAce

Angry Boss Reminders helps raiders switch to the proper talents, glyphs, and gear for each boss during a raid.

Sheppard

Makes those pesky garrison animations go away.

MendWatch

Bidder for DKP points. Usable as standalone bidder, or with DKP - Manager to manage points.

Resizes some default UI frames (GuildUI, LootFrame, RaidInfo, TradeSkillUI and TrainerUI) to show more lines

Keeps track of HoTs, DoTs, Buffs and Cooldowns. With audio and text alerts to refresh them.

FuBar_CombatTimeFu

Numen

Sphere

Tracks profession specific cooldowns and items across all your characters

Keeps track of your reagents for buffing.

Manages tracking of raid attendance, loot, and more.

Calculates incoming damage avoidance and mitigation

Niagara

OneChoice tries to help you reduce quest reward choices down to, ideally, one choice.

Monk Brewmaster/WindWalker Priority and Buff/Debuff Tracking Tool

Adds talent specialization role status to Grid.

Powerleveling guide framework

Rep2 displays a message, which shows how much reputation you gained, and how much is needed until the next standing.