GOG continues taking a leaf out of the book of Steam with their own little demo festival, along with a big sale on tons of games. On the Linux native side, the demo selection is a bit barren and it's the same for their upcoming games list but no doubt you can get plenty of them working with Wine. There's plenty of tools available to help with that, like Bottles.
You can see all their Linux games on sale here. For a few picks these are great:
- This War of Mine - 80% off
- Rogue Legacy - 75% off
- Neverwinter Nights: Enhanced Edition - 70% off
- The Darkside Detective - 68% off
- Children of Morta - 60% off
- BEAUTIFUL DESOLATION - 55% off
The GOG Games Festival ends April 4th, 1 PM UTC.
ICYMI: the GOG team also announced some changes planned.