8. Napoleon
It's no secret that Stanley Kubrick was a huge Napoleon enthusiast, and in the late 1960s, endeavoured to get an epic, three-hour biopic of the man rolling. True to his typically meticulous, obsessive eye for detail, Kubrick is purported to have read hundreds of books about the ruler as well as having consulted with world-renowned historians. Furthermore, his picture would have ideally had tens of thousands of extras for some mind-meltingly ambitious battle scenes, which surely would have been an awe-inducing sight (and with CGI'S now pervasive use, one we'll never see in the same way). If this absurd level of ambition wasn't enough to put the scares on studio executives, then the fact that three films about Napoleon beat Kubrick to the punch - and more to the point, all catastrophically bombed - such that MGM laughed at the idea of sinking what would have been a titanic budget into funding Kubrick's lunatic, potentially brilliant odyssey.