You have access to a number of different data points -- cookies, IPs, language accept sets, etc. The difficult part is deciding what you want to pivot on. Als

You have access to a number of different data points -- cookies, IPs, language accept sets, etc. The difficult part is deciding what you want to pivot on. Also helps to know the limitations of each of those methods (e.g. IP addr isn't always accurate, especially not withing 15 miles or so, but it's decent at guessing countries).