I am using -
Xperl - Unitframes, all kind of unitframes
Skada DamageMeter - counts fight by fight, total/overall, can tell u which attacks/abilitys u used in the fight, and what kind of dmg. they have made. Also tells healing, deaths, threat and everything
Bartender4 + ButtonFacade + ButtonFacade Serenity - Bars
OmniCC - Cooldowncount on the buttons on your action bar
SexyMap - skins to your minimap
Chatter - Chat + Combat Log
TitanPanel - Informationbar
Bonuasscanner - tells you about your STA, INT, SPI, SPELL POWER, ETC.
RangeDisplay - Tells you how far u are from your target
Carbonite Questtracker - Quest and Leveling add0n
ShieldMonitor - Tells you how much dmg. the shield can take, and shows a timer for, how long time the shield is staying
Elko's Buffbars - Show Buffs/Debuffs and what you are tracking

Not Shown add0ns -
Atlas - Map over Dungeons/Instances/Raid + the drops from the PvE thing, you are doing
PriestFriend - Sounds for your buffs and /macro with Jokes, when u mount.
Ex. *Cough Cough* I wish my (MountName) didn't Smoke that much.
If it wasn't for my (MountName), I would be running.