Die2Nite is a browser game of survival set in a hostile world inhabited by zombies. This game is one of the very best for having people come together. There are a lot of different ways you can play the game. If you are going to be selfish, you need to be sneaky doing it for the most part. That is a strategy in itself. Every real-world night the village gets assaulted by zombies, and every day the lot of you head out into the desert to scavenge for items and use them to build anything from walls to guard towers to workshops.
The players are divided into groups and are allocated a small town where they must organise themselves each day in such a way as to survive as long as possible against these beings. Objects and materials found by the citizens can be shared. During the day, citizens can leave the relative safety of the town to explore the desolate wastelands of the World Beyond to find weapons, materials and food.
You get 6 action points to start with when you awaken and these can be spent walking around the world, searching for useful objects and helping out with construction tasks around the town. There are a lot of useful items out there that are needed to build additional defenses but strangely it felt like we were always, always short of "twisted planks".