I'm still amazed by what people build in Minecraft, the famous open-world game. Here is my latest coup de cœur, an adventure map set in Paris, created by Stratocrafteur. Here's the trailer :
Download the english version here (planetminecraft), or the original, in French, here (minecraft-france.fr).
The Yogscast did a fun walkthrough of the map, here are the videos : part 1, part 2, part 3 & part 4 (the other parts are not up yet).