Travelers to Japan should be warned that it can be a nightmare trying to buy a sim card for calls and data usage. And unlike Korea, free Wi-Fi spots are a bit of a rarity. The good news is that from October train operator JR East is offering free Wi-Fi internet at its travel service centers at both Narita and Haneda airports and Tokyo Central Station, as well as at all 13 stations on the Yamanote line. Each connection lasts up to three hours. More info at www.jreast.co.jp