Giant Spider From Outer Space is a set of free rules for a solo game inspired by B-Movies.
Urban Dead is a free MMORPG where you play the survivor of a zombie outbreak. It’s got a huge following among gamers of all kinds.
Arkham Investigator is a free tabletop game of Mythos mystery. From the Board Game Geek description:
Welcome to H.P. Lovecraft’s Arkham, the 1920s. There will be many mysteries to uncover in this storytelling game of Lovecraftian terror. Using the provided newspaper, a list of allies, the directory of Arkham residents and a map of Arkham – your job is to follow the clues from location to location, suspect to suspect – to unravel the mystery and answer the questions posed at the end of each scenario.
Your score will depend upon the number of clues points you needed to visit, the risks you took to your sanity in your investigations and your ability to find the correct answers to the questions.
Match wits with Armitage’s final score the man who has been exposed to the sanity-blasting truth about the existence of the age old evil! Can you beat his score?
With that in mind it is time to collaborate with Armitage’s investigations to complete your training. This is not a typical board game: No dice, no luck, but a challenge to your mental ability.
Entrenched is a set of free wargames for the early years of the First World War. It is designed for 1:76 scale figures.
Corpse Craft is a beautiful and addictive video / flash game that combines a Tertris like puzzle with a building strategy game. In it, you accumulate the resources of blood, flesh, scrap and energy by completing a Tertis like puzzle. When you have enough resources, you can then unleash different types of Zombies to take down your mad scientist rival.