Movies and gimmicks; we've had a good few. 3-D, Emergo, Shock Sections, Hypno-vision, Duo Vision, Hypno Vista, DBox, Psychorama, Percepto and Sensourround to name but a few but surely the most bizarre gimmick has been to use the viewers sense of Smell. I saw Polyester at The screen on the Green in 1981 and was lucky enough to experience Odorama in all it's dubious glory. I seem to recall that each smell was indistinguishable from the next. Here are some other examples of the smell of cinema, or should that be The Cinema of smell?
ODORAMA card for Polyester
Aroma -Scope for Spy Kids 4