Cameos are a great way for directors make reference to a film's history, like in Robin Hood, or to work with a legend like Bill Murray because they can. Here's five of the best...

HARVEY KEITEL / PULP FICTION

How slick was Harvey Keitel in this? He pulls up in a sports car. Wearing a tuxedo. At, like, ten in the morning. Slick, I tells ya. Quentin Tarantino specifically wrote the role of Winston Wolf for him after he basically funded the production of 'Reservoir Dogs' for him. He's only the screen for the better of ten minutes. There were a couple of deleted scenes involving 'Monster' Joe - fun fact, the 'Monster' Joe they're referring to is 'Gremlins' director Joe Dante. How do you take it, Mr. Wolf? Lots of cream, lots of sugar.

BILL MURRAY / ZOMBIELAND

When Bill Murray turns up in anything for a short role, be it Curly Sue, Garfield, Charlie's Angels, he instantly lifts everything up with him. Zombieland was a pretty funny film to start with; you have Woody Harrelson being Woody Harrelson, Emma Stone in the role that pretty much made her and Mark Zuckerberg / Jesse Eisenberg. Who's funny. I guess. So, it's the zombie apocalypse and they're hiding out in Los Angeles. Where do they decide to visit? Bill Murray's house. Who's there? Bill Murray in a zombie outfit. It's his house, isn't it?

PAUL SIMON / ANNIE HALL

If you've never seen Annie Hall, really - make time and watch it. It's nowhere near as pretentious and shit as you think it is. It's actually very, very funny. Woody Allen is an angsty TV writer who starts a relationship with a wispy club singer played by Diane Keaton. After one of her gigs, a totally chilled-out Paul Simon comes over and tries to convince her to "come and have a drink with me and Jack (Nicholson) and Angelica (Huston)". It's blink-and-you'll miss it but he totally nails that sleazy record executive-speak down pat and, y'know, it's Paul Simon.

SEAN CONNERY / ROBIN HOOD, PRINCE OF THIEVES

True story - Sean Connery played Robin Hood once in a film in the 1970's with Audrey Hepburn, who's now in those Galaxy ads. We all remember this film for the soundtrack, Kevin Costner and Christian Slater not even attempting an English accent, Morgan Freeman as the sidekick, the Bryan Adams song, Alan Rickman being Alan Rickman - but the cameo right at the end by James Bond was a fantastic way to finish the film off. “If anyone objects to this marriage, let him speak now or forever hold his peace.” Sean Connery objects. Because he's Sean Connery.

MIKE TYSON / THE HANGOVER

Mike Tyson's tiger. In The Air Tonight. “I'm just sayin', that was Mike Tyson. He's still got it.”