The Bourne Ultimatum managed three weeks at the top of the UK box office. The Simpsons Movie, Shrek The Third and the latest Harry Potter managed just two weeks apiece. So it is with some amazement we report that Run, Fat Boy, Run has slogged its way to the top spot for four weeks in a row. The latest salvo of new movies – Halloween, George Clooney thriller Michael Clayton, Jodie Foster revenge flick The Brave One, Seann William Scott comedy Mr Woodcock – all faltered at the starting gate at the weekend, while Simon Pegg has just kept on running. The other big success story is Atonement – the box-office runner-up once again. Released on the same day as Fat Boy, it has taken more money overall, despite never beating its comedy rival on any weekend. The reason? Big takings on weekday evenings for the Keira Knightley weepie. Can the Brit film hit duo hold their own against Ben Stiller in The Heartbreak Kid this weekend? We doubt it…