How do you answer Facebook's hiring question about your very best day at work?

'On your very best day at work - the day you come home and think you have the best job in the world - what did you do that day?' social network asks prospective employees

Technology companies are notorious for favouring impossible job interviews. Google's questions range from logic puzzles ("how would you weigh an elephant without using a scale"?) to puzzles of a different sort altogether: it asks would-be music curators to put together a playlist that would please Susan Boyle fans, to make sure that they don't accidentally hire music snobs.

Facebook too has its own range of interview questions. Their technical challenges are as tough as any other Silicon Valley firm, with candidates reportedly asked to write code to find words on a Boggle board, or find sums in an array of numbers. And even non-technical jobs are given their own head-scratchers: one executive assistant candidate in London was asked "If your exec was stuck in Paris and needed to get to Milan, but their flight was cancelled and their phone was dying, what would you do?"