I wouldn't count free with preorders. There have been a lot of those and they aren't exactly "Free" when you have to buy a specific game like that. Wasteland came with Wasteland 2, There was a promo code with Randal's Monday that offered 3 different games...
And they are hardly "free" when you get them for buying a full or mostly full price game here.
I see your point of view. I'm just continuing in the spirit of Adamantios who included it in his/her list. I guess you could say that they are pre-order freebies. I might split up this list in the future :) But thanks for the wasteland one, realised it also came with Bard's tale, have added it to the list. Also added Randal's Monday
The beta of The Witcher Adventure Game was free to those who preorder The Witcher 3 and then GOG just gave beta keys to whoever wanted the game, as the beta was finished the game was removed from the library and the beta testers could buy it with a 40% discount.
Neverwinter Nights Diamond was given to anyone that preorder The Witcher 3.
One of the The Witcher 3 DLC is free
I would discount betas as they are not really full games per se, but yes NWN Diamonds can be added to this list since it was a pre-order freebie :) Thanks for this!
I'm still contemplating if free dlcs should be included in this list, but thanks for the headsup