Norway is a different case from most of the rest of the world, we run what's called an IT network earthing system where there is no neutral lead. Everything is connected between two phases getting 240v, and the earth wire is tapped from an actual metal rod dug into the earth.

This setup is pretty much a mess, and can wreak havoc on laboratory setups, so e.g. at universities all the lab rooms are laid out with TN (the standard everyone else uses). This means you can mess stuff up in the lab by running an extension cord from the adjacent non-lab room (e.g. get large ground voltage differences, all sorts of wanky stuff).