Some recent social game developer auctions on eBay:

Early Intervention Games : Fun, Joyful Ways to Develop Social and Motor...

$19.83
End Date: Sunday May-20-2018 21:16:25 PDT
Buy It Now for only: $19.83
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Flash Game Development In a Social, Mobile, and 3D World, Paperback by Gladst...
$42.44
End Date: Friday May-4-2018 2:23:25 PDT
Buy It Now for only: $42.44
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Nashoba's WH Board Game Social Skills Development Autism Spectrum Disorder New
$24.99
End Date: Friday May-18-2018 0:52:12 PDT
Buy It Now for only: $24.99
Buy It Now | Add to watch list