The only movie I remember seeing in 3D is "My Bloody Valentine", and the audience screamed and covered our faces when the swaying sickle/ax or whatnot purtruded from the big screen. That changed in June, when I saw "Flight of the Butterflies."
The documentary is a little on the creepy side -- rather, the creepy-crawly side. In some scenes, a single monarch butterfly or its caterpillar overwhelms much of the screen...
... and it was in 3D.
and I watched in a small, intimate theater.
And I was the only audience member for that showing.
And there's at least one scene with amplified sound of a monarch larva feeding on its shell.
It's kind of gross...
... but kind of cool, too.
Full review at landturn.com/reviews/flight-of-the-butterflies