In the comments of yesterday's edition of The Queue, Gilgamesh mentioned that you're actually able to attack the projection of Mr. Bigglesworth in Wintergarde Keep, or at least, you could for a long time. It's inspired me to... tell a little story.
Once upon a time, The Queue was Ask a Beta Tester. We were still in the midst of exploring Northrend before every Joe and Jane could waltz in there, and I was a puny level 71 traipsing all over the world and taking in its beauty. Ohh! Dragons! Ooo! Yetis! Oh look, hehe, there's a kitty on the projector! Let's click on it!
Oh no! Oh nooo! It's attacking me! Oh gosh, it's just a critter, I can just 1-shot it. Unfortunately for me, it was level 80, and I was a level 71 caster. It resisted absolutely everything. I ran around Wintergarde flailing my arms in horrified desperation, hoping and praying it would leash and leave me be. Unfortunately, it did not, but I had healing spells and managed to weather its furious paws until my Prot Paladin friend showed up to tank it for me. Not my proudest moment, that's for sure.