I've recommended Adam Curtis's documentaries on here a few times and I'm about to do so again! His recent series All Watched Over By Machines Of Loving Grace was brilliant. The three episodes explore the power of the machine and the computer as a model of the world around us. Sadly they take these off the BBC website very quickly, I hate that the BBC produce so many interesting documentaries and programmes and don't allow people permanent access to them on the web. Luckily plenty of people have uploaded them to YouTube so you can watch them there.