Since Priscila Leite and Isabella Velletri set up Homestaff, a domestic-employment agency, three years ago, they have been contacted by 5, 000 would-be mistresses and have been able to find staff for 650.

ECONOMIST: Domestic labour

By the late 1800s the Royal Yacht Squadron had become a social nexus abuzz with the beautiful mistresses of King Edward VII and with American heiresses on the prowl for British aristos.

FORBES: Old Gaffers

But Mr Ozawa's fortunes fell this week when it emerged that his wife had written to his closest supporters about his two mistresses and his illegitimate child but, more crucially, had berated her husband for taking months to visit the disaster-affected areas of Iwate, his home prefecture.

ECONOMIST: The prime minister has most foes on his own side