A lot of different keys

Abyss Odyssey
Amnesia: The Dark Descent + Amnesia: A Machine for Pigs
Aquaria Steam key
Batman: Arkham City - Game of the Year Edition
Batman™: Arkham Asylum GOTY
Batman™: Arkham City GOTY
Broken Age
Brothers: A Tale of Two Sons
Cave Story+
Cogs (not sure)
Combat wings: battle of britain
Contagion x3
Crayon Physics Deluxe (not sure)
Dagon: by H. P. Lovecraft - The Eldritch Box DLC
Deadlight
Dear Esther: Landmark Edition
Draw Slasher
Fez
Gone home with soundtrack
Gunpoint
Insanly Twisted Shadow Planet
Insurgency
Just cause collection (1+2)
Legend of Grimrock
Limbo
Mark of the Ninja
McPixel
Monaco
Nightsky
Oddworld: Abe's Oddysee®
On the Rain-Slick Precipice of Darkness, Episode One
Painkiller Overdose
Painkiller: Black Edition
QUBE
Resident Evil Revelations
Ryse: Son of Rome
Serious Sam Double D Steam Key
Serious Sam: The Random Encounter Steam Key
Shadow Warrior: Classic Redux
Shank
Shdowrun Returns
Skullgirls 2nd Encore
SpaceChem
Superbrothers: Sword & Sworcery EP (not sure)
Swords & Soldiers HD (not sure)
Teleglitch: Die More Edition
Terraria
The Last Remnant
The Swapper
Titan Quest
Trine 2 Complete Story
VVVVVV
Warhammer 40,000: Dawn of War
Zeno Clash
Zombie Shooter
Zombie Shooter 2