As the worlds of video games and movies become more entwined, the more difficult it gets to tell them apart. Nowadays blockbusters in both fields cost roughly the same amount to make, sell as much as each other, and both star Kevin Spacey. The plots in video games begin to resemble films, as action sequences in films begin to resemble video games. For the most part the line between the two remains relatively strong in that, well, there's yet to be a film where your decisions affect the outcome of the ending (Clue aside) - but the blur continues as more and more "proper" actors start lending their likenesses and voices to games. Spacey's appearance in Call of Duty: Advanced Warfare is just the latest in a long line of those tempted by the decent pay packet and probably the smaller amount of work needed to just fart around on a motion capture stage for a couple of days. The Elder Scrolls series has starred Patrick Stewart, Sean Bean, Terrence Stamp and Christopher Plummer, and Grand Theft Auto has leant heavily on tinsel town talent like Samuel L Jackson, Ray Liotta and Dennis Hopper. That's a leap that makes sense: it's just another avenue for actors to get work. What's weird is when celebrities start appearing in video games as themselves. Not stuff like Shaq-Fu, or Kim Kardashian: Hollywood - those vanity projects sold entirely on the celeb's name, rather than the quality of the title - but times when celebrities just sort of show up in video games. Like the equivalent of Bill Murray's walk-on part in Zombieland, except you could be the one to shoot Bill Murray. Chat show hosts in The Sims, pop stars on the Dreamcast, Snoop Dogg - all of these and more make up ten incredibly strange celebrity video game cameos.