Any of you gentlemen play Minecraft?
It's an Block-based indie construction rpg, currently in alpha, being developed by a swede called Notch. It has a large online community and can be played offline in survival mode as well. It cost's only 9€ for the full version, which gives you access to the latest version of InDev, which has many features that regular survival mode doesn't. I seriously recommend checking it out: http://minecraft.net