I like Nicolas Cage movies that are dark and edgy. His is such an odd delivery that he seems to really connect with characters who struggle with moral dilemmas (think Raising Arizona and Leaving Las Vegas...not Valley Girl). That's the biggest reason I enjoyed Lord of War.
Lord of War follows Cage's character as he becomes the most successful arms dealer in the world. The film isn't really about that, though. It is really about how the character handles success, what (and who) he is willing to sacrifice for money and power and how those around him are affected by his greed. Cage delivers the moral angst with such conviction that, while watching, I found myself curious if the film was based on fact.
I'm highly recommending Lord of War. Check it out. ***1/2