I remember back in '88 our school went on a field trip to The Science Museum where they were featuring a Hollywood Monster prop exibit. Of the two that stood out for me were the animatronic wolf head from An American Werewolf In London and the almighty queen alien from Aliens.
She was in the center of the museum posed fighting with the powerloader. Her tail was suspended around the whole exibit. I swear to God it was 100 feet long. My 14 year old jaw dropped to the floor. It was other worldly. The only other time I felt like that was witnessing the Pieta in St. Peter's Cathedral at the Vatican.
It's a shame kids today can't witness the awe that practical film magic can bring. I doubt the exibit would have been the same with a hard drive that designed the Na'Vi placed in the center for all to marvel at.