Enzo Ferrari's cars ruled sports-car racing, Le Mans especially.
 
At the start of the decade, he had won the famous and gruelling 24-hour race three times on the trot. However, the company was in deep financial difficulty, so when Ford offered to buy the entire business, Enzo agreed.
 
And on May 21st 1963, Ford executives arrived in Maranello to sign the deal. Ford turned up with an army of suits. Enzo Ferrari sat opposite them with just the local town lawyer. They read the contract and all seemed well, but then, suddenly, Ferrari stopped and he took out his famous fountain pen full of purple ink, and as you can see from this accurate copy I have here, he drew a big exclamation mark and he wrote, "No, that's no good!" - James May, The Grand Tour

Need I say any more? Diamine's Imperial Purple is rich, deep, and regal, adding a flourish to any notebook, lecture notes, scrap paper, or contract you put pen to paper on.