Some recent serious games auctions on eBay:

Serious Games Development and Applications: 5th International Conference, SGDA 2

$91.79
End Date: Tuesday Feb-6-2018 16:39:52 PST
Buy It Now for only: $91.79
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Serious Games: First Joint International Conference, JCSG 2015, Huddersfield, UK
$91.79
End Date: Tuesday Feb-20-2018 16:24:52 PST
Buy It Now for only: $91.79
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Serious Games and Edutainment Applications (2014, Paperback)
$136.19
End Date: Friday Feb-2-2018 22:47:11 PST
Buy It Now for only: $136.19
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Serious Games for Healthcare : Applications and Implications (2012, Hardcover)
$245.00
End Date: Thursday Feb-8-2018 7:36:05 PST
Buy It Now for only: $245.00
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