The Indiana Jones of Economics, Part III
Reading through the comments there are a surprising number of comments made by people without a correct understanding of Giffen Good, though clearly there are also people that do. Now my dear ECON 100A students if you have studied the material well you should be able to point out their mistakes, for example:

1. Don’t understand that the correct measure of price is opportunity cost.
2. Don’t understand that the effect of Giffen Good comes from the income effect of the price change.