Some recent serious games auctions on eBay:

Serious Sam Advance (Nintendo Game Boy Advance, 2004)

$12.99
End Date: Thursday Sep-14-2017 16:09:02 PDT
Buy It Now for only: $12.99
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Serious Games: Games That Educate, Train, and Inform David Michael, Sande Chen
$5.29
End Date: Sunday Sep-10-2017 13:54:41 PDT
Buy It Now for only: $5.29
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