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 - Steam Trade

Castle Crashers - 3 keys

Forge - 1 key + 2 ref

The Showdown Effect - 1 key + 4 ref

Games - Steam Keys

Planets Under Attack - 1.33 ref / craft hat

Iron Grip: Warlord - 1 ref

Uplink - 0.88 ref

Darwinia - 0.88 ref

Dynamite Jack - 1 ref

Nightsky - 0.88 ref

Solar 2 - 1.11 ref/ craft hat

Sword & Sworcery - 1.11 ref/ craft hat

Splice - 1.11 ref/ craft hat

Crayon Physics Deluxe - 1 ref

The Basement Collection - 1 ref

Cave Story + - 1 ref

Offspring Fling - 0.55 ref

Closure - 0.77 ref

Snapshot - 0.77 ref

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)