So.... nothing to do about key scam ?

I scammed by this bastard over here (already banned. It's my fault for not checking out.): http://steamrep.com/search?q=http://steamcommunity.com/id/Arkhanda

I created an account here to report him and discovered there is no way to do so. That's it ? Just let him go away with that ? I'm not expecting to get my key back, but I want to add another charge to his file.

Anyone ?

I am not sure I understand your question; How is there no way to do so?

On the "report a fraud" page it says "Do not submit Phishing or CD-Key scam reports ", and when you open the options tab there isn't an option for filing key related report.

So the thing is, he is going to walk free from this one.

Did you get scammed out of a CD key?

I'll give you the TL;DR.

I posted on the Chivalry (the game I had a key for) board and said I am interested to trade it. This guy messages me, talk for a little and agree on a trade (I give him Chivalry, he will give me Hyper Light Drifter). I went first, and after getting nothing I checked him here and found out he is a know scammer.

Then I am terribly sorry for your loss but as you have mentioned, this does not comply with our investigation policy.

What you can do however is report the user to VALVe following the guide below.

1. Visit the accused's steam profile
2. Click the "MORE" drop-down located at the top right of the page
3. Choose "REPORT VIOLATION"
4. Select the violation, then describe it and provide the evidence, just like you would in one of our reports
5. Click the "SUBMIT REPORT" button.

Click here to view an animated gif that shows how to report a violation through a user's Steam profile.

Unfortuantly I don't have any decisive evidence other than the fact that he is already banned here, and I don't have the full chat log because it's not saved automatically.

Even if I did, Valve's policy is "didn't used the trade system ? It's your problem, mate. And we don't really like the whole key trading, anyway." isn't it ?

You would be surprised how happy they are to take out scammers and reporting them never hurts.

Exactly. VALVe does not give chargebacks. If you trade something, it is your own responsibility. They made a trading system which is quite good for items.
If you want to trade, you should use this systems and no 3rd party websites and/or other methods. VALVe has a 2 factor authentication on it. As you 'gave' the game to him (that's what support will say if you contact them) Steam will not take any action.

It's always advised to trade with caution. It's your own responsibility to do research. As you said for yourself, the trader was a known scammer. If you had checked BEFORE trading, this (maybe) would not have happend.
Take some lessons out of this for any future trades.

Check out this guide made by Lava to prevent any future problems with trading.

Well I just did it. I hope they will take care of the bastard.

The question has been answered. Locked and archived.