Rumour has it that in the backgroud of this scene, you can see a munchkin committing suicide, either because he wasn’t awarded a role of a munchkin or because of unrequited love from a female munchkin.
Look carefully at the trees in the back, and you’ll see something moving around.
According to snopes:
At the very end of this sequence, as the three main characters move down the road and away from the camera, one of the larger birds (often said to be an emu, but more probably a crane) standing at the back of the set moves around and spreads its wings. No munchkin, no hanging – just a big bird.
How boring is that! I want conspiracy theories! I want suicide in the Wizard of Oz movie! I don’t want big bird! *stomps away to sulk*
When Insane Author Number 1 and I were discussing this last night, we compared it to the movie BlowUp. In this movie, a photographer takes photos in a park, and when he blows them up, he thinks he sees a man with a gun in one photo (the trees?) and a body in another (a grassy hill?). And he sets of to investigate. At the end of the movie, you are still not too sure what you (or the photographer) has seen (or not).