I'm linking to the Top 10 Movie Gimmicks, only so I can wax nostalgic about one of them - Sensurround - a technique which gave the illusion that the theater was shaking.As far as I know, it was only ever used in two films - Earthquake and Rollercoaster. I saw them both, and even saw Rollercoaster twice.
I didn't realize Earthquake was such a dreadful movie at the time (Lorne Greene plays Ava Gardner's father for chrissakes) - I was too fascinated by the brief sequences where the theater appeared to be shaking. It was the moment in my life when I first discovered the term "richter scale".
Rollercoaster was a much better movie. A real gem from the '70s about a mad bomber who blows up rollercoasters - starring George Segal as a detective. I actually saw this twice, and then watched the non-Sensurround version when it played on TV.
Turns out "Sensurround" was a bit of a rip-off; just an exaggerated loud sound that made the seats vibrate. (And I always thought the theaters had to be specially wired!)
