I have a bunch of extra steam keys from bundles I purchased and already owned some of the games.
I'm selling them for TF2 items, other games and offers. These are all steam keys and therefore can not be traded through steam trade, so one person will have to go first.
You can check my Profile and see the amount of rep I have there and my steam rep to verify I'm not a scammer, here is a link to the page I have sold items for Paypal with happy customers, so unless you have good rep, I'll expect you to go first.

Games

Bioshock - 2 keys

Dota 2 - 0.33 ref

Trine - 2.33 ref

Home - 1.55 ref

Titan Quest - 1 ref

Warhammer 40,000: Dawn of War - 0.88 ref

The Basement Collection - 1 ref

Cave Story + - 1 ref

Offspring Fling - 0.55 ref

The Bindings of Isaac + DLC - 1 ref

Closure - 0.88 ref

Shank 2 - 1.22 ref/ craft hat

Snapshot - 0.88 ref

Bundles

Darksiders, Red Faction: Armageddon, Metro 2033, Company of Heros, Company of Heros: Opposing Fronts, Company of Heros: Tales of Valor + Red Faction Path of War DLC - 1 key

I will do deals for multiple keys and I accept most TF2 items(They just have to be close to the value of the prices)