I love Good Old Games. Their client, GOG Galaxy, is completely optional and endearingly user-friendly and seamless. They offer a ton of my favorite classic games that are guaranteed to work on modern operating systems. And for the past few years, they've had some killer sales. Now their 2016 summer sale is finally here and they have a big incentive to dive in: for the first 48 hours, System Shock 2 is completely free when you log onto GOG Galaxy!
That's right, in addition to all the great deals, Galaxy users can score Shock 2 for absolutely nothing right now. In addition, completing tasks similar to what you'll see in a Steam sale will earn you XP, but the GOG twist is that XP can net you more free games. I've never seen Steam do that.
GOG's summer sale runs through Wednesday, June 22nd--both sneaky and polite, considering Steam's big summer sale kicks off the following day. I love Steam and I have a huge backlog to work through there, but more and more I'm becoming loyal to GOG and their customers-first business policies.