Someone on Ubuntu-fr forum gave me this link : http://www.netblender.com/main/
You can download, for free, an iso image of a Demo 3D Blu-Ray !
You can "mount" it with a software (I don't know an english software which do this, sorry).
The video is real HD and 3D
I hope it's in the right forum.
I apologize for my english, I'm just a young french
(If you find some mistakes in my English, tell me, so I can learn ^^)