The latest gadget released to the Japanese market by Emobile looks great to me. It is a device that fits your pocket and connects to the Internet via HSDPA anywhere in the country at 7.2Mbps, without being plugged to any computer, and then generates a 802.11 Wi-Fi signal.
In other words, if you have the Pocket Wi-Fi by Emobile you will be able to surf the Internet with any Wi-Fi device you have. You can enjoy it for only 45 euros per month with a flat rate (no bandwidth restrictions are applied).
Explanation that shows how with the Pocket Wi-Fi you can connect to the Internet with any device.