Update: It is given away.
I was so lucky to receive a code from a random passer by, and as I was told I could give one on myself, I thought I’d pass it on.
Therefore, if anyone would like to try and buy some Good Old Games from GOG.com, feel free to ask me for a invite code. First come, first served. My email address is made up from my handle “tormodh” and the domain of Google’s popular email client – “gmail.com”, or you could drop a line in the comments below. Email entered in the field (for email) will not be shown to others than me.
More info (same links as supplied by Mart):