And to begin they're offering up free copies of System Shock 2 to everyone for the first 48 hours of the sale! Which, in case you need reminding, is an absolute classic. In order to claim your copy you'll need the GOG Galaxy client but that's no big deal. Also checking in each day, buying games, and doing things like adding games to your wishlist will also earn you XP, leading up to free copies of games like Gabriel Knight remastered and even Dreamfall Chapters. Which, is pretty awesome. Oh, and there's also a bunch of games on sale.
Like The Witcher III: Wild Hunt at 50% off for $33.99, Day of the Tentacle Remastered at 33% off for $13.39, and the LucasArts classic bundle featuring 10 games at 75% off for a mere $23.50. And with over 100 titles discounted and all DRM-free this is definitely a sale that you should keep an eye. Check it out