Making a good movie is difficult enough, let alone a great one or, better still, one that actually changes the landscape of cinema forever more.
Without The Jazz Singer we wouldn't have sound, without The Wizard of Oz we wouldn't have Technicolour, and without Toy Story we wouldn't have CGI animation, to name just a few key innovators.
But beyond those precious few films which genuinely changed the game, there have been dozens of pretenders who admirably tried to give viewers a totally new type of cinema, yet categorically failed in their attempt.
Whether met with a hostile audience response, commercially unsuccessful or simply failing to skyrocket in the way the filmmakers hoped, these various technologies and efforts to spruce up the moviegoing experience became curious novelties at best, if not actual embarrassments.
It remains to be seen which new gimmick will be shovelled into cinemas next, but in the meantime, these are the most outlandish and ambitious that have yet been attempted...