Right now in the Mists of Pandaria beta, hunter pets have an interesting bug where they retain their pre-tamed size. As you can imagine, this causes a lot of fun and confusion in town when hunters pull out their King Krush and Chromaggus.
But my favorite stupidly huge pet in the MoP beta, bar none, is Terokkarantula.
With the help of Wassa in the Petopia Community MoP forum, allow me to demonstrate:
Just imagine the amazingly terrible horror movie you could build around that screenshot!
And in the same thread, Spiritbinder shared this adorable comic:
I’m embarrassed to say it took me a good thirty seconds to spot the hunter!

http://www.wow-petopia.com/look/raptor_outlandgreen.html
I have the Felsworn Daggermaw. When I logged into the MoP beta and called him out, I had forgotten how big these guys are in their pre-tamed state.
It’s a fun thing to show off, but completely impractical for actual play. Fortunately I do have some pets who are more manageable :)
Reminds me of Sim City, somehow… great screenshot! :D
Not more spiders…. i hate spiders… also in PvP when Hunter Pets come over you ;-)
My hunter in the beta has the white Sons of Hodir wolf, the one that sits beside the King. It’s maaaaaaaassive.
I love it, it’s so fun!