I don't remember seeing this mentioned anywhere else, so I thought I'd share. I have found a few sites hosting giveaways in partnership with GOG on occasion of the Halloween sale:

PC Gamer (300 horror-themed games)
Techraptor (50 spooky games, divided into two giveaways)
Adventure Gamers (12 classic Sierra Games, plus a grand prize with 8 different games for one lucky winner)

Good luck to everybody!

Quick reminder of the last chances to participate: there are less than 6 hours left to enter the PC Gamer giveaway, and less than 24 hours for the Techraptor ones.

The Adventure Gamers giveaway will still be around for five more days.

Thanks for sharing :D

Got the email earlier that I won something from one of them. And much to my surprise, it wasn't Psychonauts or Syberia or a game I'd otherwise purchased at some point here.

I was lucky enough to win a game both at PC Gamer and at Techraptor! I sent the keys to finkleroy for the Community Giveaway.

BTW, only 15 hours left to try your luck at Adventure Gamers.

Very magnanimous of you. I take it they were games you'd previously purchased or ones that fell out of the range of your interest?

Also, I don't remember but were any of these (supposedly) US only?

One I owned, the other I wasn't gonna play anytime soon.

I didn't check the terms this time, I remember a previous giveaway with the "US residents" clause but people outside the US did participate without restrictions. After all, you enter with just an email address.

Yeah, it was the one run by IGN I believe (the one where I ended up with a copy of Syberia that I couldn't get rid of before the time it expired, unfortunately).

(edit: Or was it Gamespot... I don't know anymore, they all kinda blur into one indistinguishable blob after a certain point)

I wonder why they bother with that restriction at all, since even if it were more actively enforced through some other means it'd just prompt people to enter through VPNs that happened to live outside the specific country anyway. Unless they want people to believe that whoever is in charge of drawing the winners is going to sit there and examine IPs of every individual entrant or something equally silly like that.