Be sure to check out this link sent in by machinasa which has all sorts of information regarding how to shrink your character. And thanks, of course, go to The Minimizer for permission to link to the site's WoW page.
There's an item in World of Warcraft called the "Elixir of Giant Growth". It increases your characters actual size while boosting strength to match. (raiden_nu)
If your character is in the Engineer profession, he/she can build something called the Gnomish Shrink Ray. It's a trinket class item and its use is to shrink the enemy and their group if they have one, decreasing their stats. However, sometimes it backfires and its been reported that your own party may shrink as small as the size of a boot, decreasing your own stats, or actually enlarging your party and increasing your stats. (Nem)
Once you reach level 45, if you can get a higher level friend to travel to winterspring for you, there is an item called Winterspring Firewater. Which makes you bigger and gives you a bonus to attack power for 20 minutes.
Also around level 45 there is an instance named Uldaman, in this instance there are many large monsters and such however, One stands out. The second major boss you fight happens to be a Giant woman by the name of Ironaya. In order to fight her, you must kill the 3 lost vikings and get the staff from the chest they guard. ( You'll know it's her area by the little town near the door she comes out of. How well placed.)
Heh the last thing just so happens to be a level 45 quest also. In Gadgetzan in Tanris there is a goblin by the name of Marin. Talk to him and get this quest to find him an item in the desert, once you return to him, he asks you to bring it to a woman in town. Do this and then there is one last part to do. Head to the hinterlands and get a mushroom to make it taste better. Once you bring it all back to Marin he makes an item called the Noggenfogger elixr and when you drink it three things may happen. You'll gain the slow fall buff, You'll turn into a skeleton and be able to breathe underwater or you'll shrink to a really small size and gain a small little speed boost, the shrinking lasts for 10 minutes. (Dark Raptor)
I know yall already know about the "elixir of giant growth" the witch doctor that makes you bigger, and the noggenfogger that shrinks you, and not to mention the shrink ray, that can make you bigger or them smaller, or you smaller ^^
anywho, I have stumbled upon ANOTHER that can enlarge you, and even stacks witht he growth of the shrink ray! Winterfall Firewater, it's a highlevel item, level 50+ drop, but enlarged about 10-25% larger, and gives +35 attack power, and lasts for 20 mins, unlike the growth potion which was only 5 mins. ^^ (Dark Vulpine)
There is 1 more method from what I have seen. It is an item that is called "Enlarge the world" which basically makes the entire world bigger but you. So it makes you look like you shrunk. It comes from being a very high level gnomish engineer to be able to make it. (eortorrisi)
Not sure if anyone has said anything to you about another item from World of Warcraft, But it's called a Deviate fish and on chance it shrinks you. (Dark Raptor)
For those who may be interested there is yet another VGGTS in World of Warcraft. She's a lvl 44 elite named Myzrael and is part of a chain quest in the highlands. You can get the quest be either finding a pendant or just going up to the large black oblisk south of the East Binding Circle and talking to it. You end up getting a scroll that you can take back to the oblisk and summon her. If you end up taking a dirt nap (which I did quite a bit while fighting her) you can resummon by abandoning the quest and talking to the scroll giver again. The quest is kinda long and the reward really isn't that great, but hey, that's not what this forum is about :) (DAllen)
There's a boss in the instance Necropolis Naxxramas called Grand Widow Faerlina, looks like the normal human female except in 'normal mode' she's about as tall as a tauren or so, and every 60 or sometimes 30 seconds she enrages and becomes about twice as big or so. And hits hard enough to kill a warrior equipped in full wrath in about 2 strikes. Unfortunatly its a really difficult instance and very few people will ever get the chance to see her. (Runehoof)
In the Burning Crusade expansion there is a new monster type called Shivan. You first run into them on Hellfire Peninsula near the Legion Front in the form of "Doomwhisperers". Basically its a big blue GTS with 6 arms. There are also 2 slightly larger subjugators patroling overlooks near there. (DAllen)
I actually just found this little gem about a hour ago while playing. You
wont get to see her unless you do the quest "clearing the way" on the second
major island at about lvl 17 or 18 at the lowest possible level. its also an
escort quest, there will be a lvl 20 elite npc with you to help, but you will
more than likely need another player to help as the npc can only do so much. It
is a chain quest...this quest is the last in the chain of about 10 or so quests.
Well as for the GTS, once the npc destroys the last pillar or whatever the
Draenei sorceress unleashes her magical power and literally grows to about 50
feet if not bigger. Appearantly she was the leader of the blood elves in the
area that were controlling the sun portal and planning to take over the land,
which is the second major draenei area you enter.
No screenshots as I was in the middle of doing the quest and much as I would've
liked to admire the view sorta speak, she woulda killed me and my the guy
helping me do the quest and we would've failed. >.< On the plus side anyone with
the Burning Crusade expansion and a draenei character can also do this very same
quest and hopefully take screen shots for everyone else to see.
For those who dont know anything about WoW or just dont have burning crusade
installed...the Draenei are the newest and latest race introduced to the
alliance side of the world. (good guys) the females about 3-6 inches taller than
the female night elves and the breasts are actually a bit bigger. They look more
like humanish-tauren characters as apposed to the tauren themselves which look
like cows standing up, lol. I reccomend anyone with the game to try this quest
chain out, just for the big gts payoff at the end, lol. (TinyBlackGuy)
I ran the quest last night and confirmed it existed. The quest is on Bloodmyst Isle and is called "Ending their World". It starts at Demolitionist Legoso. You need to escort him up the coil as he blows stuff up along the way. At the top of the coil you find Sironas (Draenei) syphoning power from the coil. Once he blows up the coil, she grows to what seems like 3-4 times the normal size and attacks you. This quest isn't very hard, I was able to solo it with a level 22 paladin. (DAllen)
Burning Crusade needed. In the instance Karazhan, a level seventy, ten man raid, there is a boss, Maiden of Virtue. She is quite a deal taller than your party. If you've made it this far, you probably know enough that you can't get there alone. The instance itself is located in Deadwind Pass, near Darkshore. The trash along the way (way referring to Deadwind Pass) is anywhere from 59-70. In the instance itself, mobs are 70-72 elite; you can see where it gets hard. This instance is a commonly run raid by most guilds, so anybody with sufficient combat experience should be able to see her. Maiden of Virtue is, obviously, a ?? elite boss. The fight is really not all that difficult, but the occasional wipe is not unheard of. Her loot is geared strongly around magic, so if you have a lot of melee fighters in your party, chances are that you will not be fighting her. Good luck to the people that do reach her. (StarbucksMan274)
To access this, you must have the Burning Crusade Expansion Pack installed. Inside of a branch of the Tempest Keep, called the Mechanar, there is a specific blood elf enemy called "Sunseeker Engineer". On occasion, they will use a device on a random member of your party called "Super Shrink Ray", causing your attack power to fall sharply, along with your height. This can stack; however, the debuff only lasts for a period of ten seconds. This will work on either normal or heroic difficulty. This is not to be experimented on by any character below level seventy, as the instance can be a bit of a challenge if your party does not know the instance well. (StarbucksMan274)
I'm suprised no one brought this up, but in the new expansion (Wrath of the Lich King) there is a race of non-playable characters called the Vrykul. The Vrykul are basically half giant vikings, and there are females among their ranks. While they're almost constantly sieging Valgrade when you show up in the Howling Fjord, you start to see the females once you hit Westguard. There's a female hunter that patrols the woods, and they're all over Skorn. (DAllen)
At around lvl 8 at Sen'Jin village south of Orgrimmar you can take a quest called Zalazane. Upon completion of this quest speak to apprentice Witch Doctor Bom'bay and select a random answer. The effect is random but you can get you size increased by about half you size. Then, logout and log back in. Do it again until you get the growth again, and your size is doubled. Stack this with an Elixir and you've got a pretty big character . This logout effect only stacks twice. This is HORDE ONLY. I suggest doing it on a Blood Elf because pretty much all other Horde races are fugly.
http://www.wowhead.com/?quest=826 for the quest description. (fire_and_ice_980)
Someone at Blizzard loves us :)
At level 77 in Sholazar Basin there is a quest line starting with Pilot Vic at River's Heart (though I think you can start right from Freya), where you fly a recon flight and spot a gigantic woman fighting off scourge near the Lost Lands. From there you meet with The Avatar of Freya who gives you a chain quest to unlock some Titan weapon for battling the scourge. Freya has to be a good 40 feet tall. (DAllen)