There has yet to be a brilliant movie based on a video game. There have been many watchable ones they just never seem to get things right.
These fan made trailers show the possibilities that some of the games have if they made the leap to live action. Even those games that have already been turned into bad films. The fact they are made using footage from many different films, games and TV shows is great work.
Red Dead Redemption: Undead Nightmare
Lots more on the BloodRunsClear youtube channel.
Why has there yet to be a decent movie based on a video game? What games would you like to see turned into a film?