For every legendary fast food item, there's a graveyard of other failed innovative attempts. Take, for example, McDonald's bizarre Hula Burger. If you haven't heard of it, that's because it was a dismal flop. But its failure paved the way for the success of one of McDonald's signature non-burger items, the Filet-O-Fish.

This head-scratching concoction of a fast food sandwich, which was just a slice of grilled pineapple and melted cheese on a bun, goes all the way back to 1962. Cincinnati-based McDonald's franchisee, Lou Groen, had come up with the basic idea of a breaded whitefish sandwich to cater to Roman Catholic diners during the Lenten season, but McDonald's founder Ray Kroc wasn't so convinced that the fish sandwich was a good idea. So Kroc made a proposition: On one Friday, when Catholic diners were generally avoiding meat, Kroc would try selling his decidedly unique Hula Burgers while Groen would sell his Filet-O-Fish.

Kroc placed a side wager with his grill operator, Fred Turner, that if his Hula Burger outsold the Filet-O-Fish, Turner would owe him a new suit. After the day was over, however, Kroc would end up owing Turner a new suit because the Filet-O-Fish outsold the Hula Burger by an incredible 350 orders to a puny six. McDonald's added the Filet-O-Fish to its permanent menu in 1965, the first addition to McDonald's original menu in its entire history.