After a few quests from K3 you'll get led to the mines of these seriously frightening blue Vrykul ladies; the quests from here, in turn, lead to what may be the best questline in WotLK - but I won't go into that here. The reason I bring the area up in this column is that for all of your questing there, you get to turn into one of them! It's pretty fun running around on a gryphon that looks like a toy, with a PW:Shield that comes up to your knees. Feral druids also get the amusement of beating on things with your staff while actually in cat form (shapeshift graphics get overridden), as well as swimming through air while in flight form. That covers the two classes I've taken through the zone, but I'm sure other classes have other amusements to relate.
So how do I get one of these amazing disguises, you ask? Simple, just do the quest chain starting with "They Took Our Men!", from Gretchen Fizzlespark in K3. After a few steps you'll be speaking with Lok'lira the Crone, and from then on you'll be clad in a fetching Vrykul disguise. After you finish A Change of Scenery and move on to Brunnhildar Village, you'll automatically be costumed every time you go to (or fly over) the village, which is good, because they have some dailies that you might want to do later for a chance at the Reins of the White Polar Bear.
Unlike much of the stuff I talk about in this column, the Vrykul disguise is yours to play with whenever you want it, assuming you can trouble yourself to get down to Hyldnir village. Sadly, they're missing (among other things) a dance animation; I imagine the model could do a pretty good robot. Still, it's fun to be blue every now and again.
Disguises, shapeshifts, and costumes, oh my! Illusionary Tactics is once again your source for everything that makes you look like somebody else. If you play Alliance, be sure not to miss Dartol's Rod of Transformation - furbolg attack!