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There's a big flaw to your logic here: Macs resell for more because the people buying them are a narrow group who believes they are worth more. Plus, supply and demand being what it is, since there are fewer of them the price goes up. If the numbers were reversed and a small group of fanatics were dedicated to PCs, the exact same numbers would probably be true.
Resale isn't a great way to determine or ascribe overall value.
[This message typed on a PowerBook G4 that's ridiculously slow and crash-prone compared to my 3-year-old Gateway at home]