The difference between a good caster and a great caster? Knowing when to pop the trinkets. And when you do so, this is the one of the best you can get.

Name: Icon of the Silver Crescent
Type: Epic Trinket
Abilities:

• Equip: Increases spell damage and healing by up to 43.
• Use: Increases spell damage and healing by up to 155 for 20 seconds
• A two minute cooldown, which, I've found, goes pretty darn fast. Depending on how fast your groups move, you can usually pop a trinket at least every other fight in an instance, if not more if you take a while eating and drinking between fights.
• And as I said: trinkets are the difference between pouring out amazing DPS or healing, and just being average. If you've got trinkets, you should be using them almost every chance you get-- the +43 damage/healing on this is nice, but if you're casting, the +155 is much better. Put those suckers on your hotbars, and light them up near the beginning of the fight (just as you're about to start casting). And as most veteran players can tell you, you can use these things twice on some boss fights-- a player casting without his trinkets in use or cooldown is a player not living up to their full potential.

How to Get It: You *are* running Heroics by now, right? If you're not, that's exactly what you got to do to get this baby. G'eras in the middle of Shattrath City will take your Heroic badges and give you epix for them, so bring him 41 Badges of Justice (that's 8 and 1/5 successful Heroic Mechanar runs, or about 60 curse and stress-filled failed Shattered Halls runs, in case you're counting), and the Icon is yours.

Oh, and speaking of trinkets, here's an extra piece of Phat Loot for you: If you're a caster, and you are keyed to run Heroic Mechanar, that means you're Revered with Sha'tar, so stop by the Quartermaster, also in the middle of Shattrah City and pick up Xiri's Gift. Great trinket, easy to grab, and while the equip isn't as good as this one, the use is almost as nice, without having to pick up tons of Badges.

Getting Rid of It: You don't want to get rid of it. Even if you do, it's a trinket-- put it in your bags and keep it for later. Personally, I carry about six trinkets around with me, and every one has its own place and time for use.