Animatrix is a must for any fan of the Matrix trilogy, especially if you are into animations.
The DVD consists of 9 short stories that all happen in the world of the original Matrix movies but that are wonderfully alternative. You will see explanations of how machines were driven to mutiny and you will see other heroes than Neo.
The animation technique varies from state of the art CG (computer generated) a la Final Fantasy: Spirits within, via traditional Japanese Anime to black and white. Simply splendid.
Favorite episode? Matriculated for sure. What a wonderful animation of virtual reality.
Don’t forget to listen to directors commentary as it shows how much work and talent there is behind the animations.
=== SPOILER BELOW ===
In Matriculated, at the end. Did I see right that the (bum) lights of the machine were back to red? Does this mean that it realised the virtual reality had been fake and that love between it and a human being was not possible?