Kevin Spacey does a great job as Christopher Walken playing Hans Solo. If I am not mistaken, that is Kevin Spacey playing Walter Matthau who is playing Obi Wan Kenobi too. Not sure about the actor who plays C3P0 though... Either way it is very funny have a look!
For more of the funniest videos in the world check out The Love Boat or Prince Vs. Charlie Murphy!