I downloaded all 27 million Go games from online-go.com, aka OGS, with permission. They are available on Internet Archive or here as SGF files or JSON. You can use them for whatever you like.
archiving arch linux art backup blog book review books dead tree debian email game game design games git github hack-a-day hacks hardware linux meta minecraft music november physical piskell pixel art prices printer programming publishing recipe research review self-improvement software storage system administration throwaway timelog video game video games website websites wikipedia yearly review