This Slate article discusses the movie review meta-webiste Rotten Tomatoes. This website is of statistical note in and of itself since it compiles the reviews of many, many film critics and then provide at Rotten Tomato score based on this sampling.
The Slate article takes this data a step further by providing an interactive chart that you can use to generate graphs that track a given actor or director's career. Below, the Tomato ratings of the films of Lindsay Lohan.
When I use this in class, I ask the students if they believe that Rotten Tomatoes data should be used to set salaries or guide casting. Additionally, I like to provide my students with the 10 Ten Highest Grossing Movies for the year as well as the Top 10 Highest Rated movies (as rated by Rotten Tomatoes) of the year and describe why the two lists are so discrepant, which can spur a discussion about why this sampling technique may not reflect on the average moviegoer.