Another hidden Mickey
Okay, I've never heard anyone mention this, so I'll share my own little discovery in the Haunted Mansion. Next time your buggy goes through the attic room (with the Bride), look for this one.
As you're on your way out of the attic, the Bride is on your right hand side. There's a wooden support beam that goes from the floor to the ceiling, just before the exit out to the hill that leads down to the graveyard. It's on your left hand side, across from the Bride. Hanging on that support beam are three cooking pots arranged in the familiar shape of Mickey's head. Now, there aren't really any lights focused on that spot, since most of them are aimed at the Bride (which is where you should be looking, I guess. Rather than combing the walls looking for circles. But I digress...) so the pots are kinda hard to spot. But if you know where they are, you'll see 'em.
Again, I've never heard anybody mention this one before. So feel free to debunk me if you feel so inclined. As a side note, I drew a little diagram to illustrate this, but my profile says I can't post attachments. So if anybody would like a little visual aid, lemme know just how the heck I can post pictures. I don't even have an album, for cryin' out loud...