Subscribe and receive DRM free games in the mail. https://www.theindiebox.com/ Who would have thought this would work? Kinda seems a bit "Gimmicky" but it just might work to help Indie developers and more DRM free games to rise up. There is a chance you might receive games you already own as well. They claim full Linux support and you should probably "like" their facebook page to see which games are currently being selected. IndieBox seems very similar to GOG.com but they send you games each month in a box with a Flash Drive.