Basically the entire server would gather together. We would have a certain time frame to build something. Say 5 mins, but no one would know what we were building until the time started. So you had 20+ people waiting and then "You have 10 minutes to build an apartment building. GO!" and everyone started building as fast as they could. No plans or anything. When the time ended you had to stop no matter how much was done to look it over. It might end up being made out of 50 different materials but somehow they usually got finished and not look to terrible. It was a lot of fun.