I think that he should make another Roger & Me type of film. The subject could be Halliburton, and he can call it Dick & Me. It will be incredibly successful its opening weekend until word gets out that it's not a skin flick.
Seriously, I think that he should focus on businesses (such as Enron or the dot com bust) and the impact they have on society. Roger & Me is an excellent documentary. He just needs to avoid adding his political agenda in future projects although that seems unlikely now.