This is the country-code top level domain from Niue. This ccTLD is particularly popular in Sweden, Denmark, the Netherlands and Belgium, as nu is the word for "now" in Swedish, Danish and Dutch and it is part of the .SE Registry. Here are some points you need to be aware when registering this extension
When this domain is registered or transferred to us, we will require a personal identification number. This number may vary depending on your current situation:
If you are located in Sweden a valid Swedish Personal or Organization Number is required (format: 123456-7890).
If you are located outside Sweden your ID number (Civic Registration Number, Company Number or Passport number)
Also, if you are located inside the European Union but outside Sweden your VAT ID is required.