Christopher Nolan may have achieved mainstream success with films such as The Dark Knight Trilogy and Inception, but we shouldn't forget his earlier more indie fair.
In fact, I would have to say that personally, I still think his best work is Memento - an incredibly ambitious movie which messes with narrative structure but still remains gripping.
To honor and celebrate Memento, The Sundance Channel recently created a 24 minute documentary which explores the structure and behind the scenes wizardry that went into creating it. If you haven't seen Memento, this might not be the documentary for you, as it's chock full of spoilers:
Favorite Nolan film?