West Japan Railway Company announced that you can purchase prepaid data SIM cards on all Sanyo Shinkansen (bullet train) cars between Shin-Osaka and Hakata (Kyusyu island). The SIM card costs 2,500 yen (approximately $24) and has a capacity of 200MB per day for seven consecutive days. Please note that Wi-Fi internet connection is required for the initial set up and Sanyo Shinkansen currently does not have Wi-Fi service.

For more information, please visit here.