Reason has released a terrific series of short films entitled Great Moments in Unintended Consequences. These relate examples of government failure, where seemingly well-intended laws have negative effects that are not predicted. They are also examples of what economist Friedrich Hayek called “the knowledge problem,” that is, no central authority has complete knowledge of the all the various factors that impact supply and demand or ever will, which is why centralized decisions often fail, with sometimes catastrophic, even tragic effects.
Here are the first two short films in this Reason series, but there are many more on YouTube.