...so, there i was thinking i just bite the bullet for yet another good GOG promo and all, when i realised that *sometimes* not all games we get are great. Sometimes, maybe because there was no demo available, or because the demo/YouTube vids/screenshots were deceiving, we got a game that, while worthwhile, isn't exactly our cup of tea, in the end.
So, i was wondering: what if GOG decided to allow some sort of trade-in, within its available games? That is, if one buys a game for 9.99, and later decides that the game could be much more, and wants to get something else, wouldn't it be interesting to have a possiblility to trade in for a game of similar price?
This situation poses some problems, namely GOG couldn't problably detect if the trade-in was fair, or if someone would exploit it to get more games, rotating throughout the GOG's catalog until all games were "acquired".
In so, i'd propose a limit to the trade-ins available to each user. Say, 3-limit. Always justified (afterall, the system would be to adjust some boughts, not to be overused all the time).
On the money department, GOG wouldn't lose. Just a simple trade-in for a good = 9,99, or the other price. So, it would be a matter of GOG replacing the traded game on ones account page with the other of his choosing. For as long as there were a limit implemented, and a way to know that a gamer wouldn't just use its limit to rotate through other games (and thus, get say 3 games for free, since he could have the installers of the previous games saved elsewhere), all should work.
Any thoughts beyond this? :]

Uh, that would simply be terribly abused. People would "trade-in" their game and end up with two games, since there's no way to stop someone from playing a GoG post "trade-in."
It's not a good idea and it does absolutely positive for the people running GoG.

I had a similar idea on trading digital games.
Though if it were me, I would make it more of a trade between members rather than the conventional method of GOG buying back then reselling the games, (though that is a decent method too).
GOG could establish the market value for the game as it were, (older games released on the site have lower value, newer games have a much higher value), and then once a deal is made, GOG can do a switcheroo, (taking the difference between the values of course (or charging a premium)), then the two members get the game they want.
However, this just wouldn't work here.
If this site was like Steam, and had a closed portal and such (DRM locking that game to you), then this could be managed properly, and the method might work.

Given GOG's DRM free nature, the only way I can see that this would work reliably is if you could only trade in games you haven't yet downloaded (assuming they keep a counter for how many times each user has downloaded each game).
Although this may also open a backdoor where a user could buy some games in a promo and then switch them for games that have not been promo'd, effectively getting them for a lower price than they have ever been sold for.

Been suggested before, never gonna happen. What's to stop someone from downloading and installing a game, then deciding to trade it in without ever removing it or deleting the installer? Absolutely nothing. The only way it could work is if GOG were to introduce some kind of online activation-based DRM, and we all know that is never going to happen here.

I think the potential for abuse and the cost of implementation far outweigh any benefit that GOG would get from doing such a thing. Additionally, the costs of GOG games are low enough that a game not necessarily being what someone hoped it would be just isn't a serious deterrent to people buying the games, so implementing such a system really wouldn't bring in many additional sales for GOG.

Digital bits are not "tradable". Bits are meant to be copied, it's their nature. You copy them when you read them from the disk, when you put them on the screen. So, from my standpoint, the simple idea of exchanging bits like real "goods" is pointless and silly.
As much as pointing a finger at P2P "piracy". There's now such fucking thing like "P2P piracy" because the are no "goods" to be "exchanged", and you pay nothing to download a file (contrariwise to counterfeit disks). As I've said before, if you think differently you are a victim of the industry propaganda and you need to see a good psychologist.... But this is a bit off-topic I fear....

Almost non-existent, fortunately...

" Almost non-existent, fortunately... "
glad to hear that

Well, at least to the extent that almost none are clearly identified as being the GOG version, but there are GOG versions to be found, quite easily.

so there's a thief on GOG

I would say there is more than one, but they are not actually thieves, they did buy the game, they just uploaded it so others could "steal" it.

" they just uploaded it so others could "steal" it. "
but why?

Why do people upload games from sources other than GOG? Personally, I think its because they're just dicks, but that's just my opinion.