I took a 3 week trip to Japan from January 21 from February 12. I didn't have an itinerary, exploring as I saw fit and moving on when the mood struck me. Through the trip, I stayed in Tokyo, Tanabechuo, Kyoto, Osaka, Hiroshima, and Nagasaki.
I made several purchases before the trip:
The Japan Rail Pass (Green) is a Japan Rail (JR) pass that lets you ride most trains in Japan. My most "Japan specific" purchase that I would recommend to anyone. The (Green) designation means that it is business class (effectively), which means better seats and reservations. I bought the 21 day pass for $700.
Google Fi worked out normally. When I landed in Japan it told me that I would pay the standard $10/gig data rate and I believe $0.20/minute. Use your Wifi call if at all possible. Coverage seemed pretty good everywhere. Was able to use it on most of the high speed trains, spotty between Hiroshima and Nagasaki.
The Tortuga Outbreaker 35L was a altogether worthwhile purchase. Most compeling features is the ability to open it fully (not just from the top) like a conventional suitcase. You don't think about it, but not having to pack and unpack your backpack is a real time saver. I also thought the compartment for the laptop with easy access was convenient, as you will be taking that out on a regular basis throughout the day.
Other feature true of the 35L is that it counts as cary on in all airlines (even small planes). It is convenient not having to wait for any lugage after a long day of travel.
I used hostelworld.com. Easy to use website. Clean interface. I would book my next hostel 5 days before actually arriving. Never had a single issue. They take I think like 10% as deposit on booking, you then pay the rest upon arrival at the hostel.
I recently bought some Bose QuietComfort 35 headphones for work. This is my best product purchase of 2016. They made air travel more pleasant (shut that baby up!). They made watching the landscape flow by on the trains more moody. They gave me a slight taste of home when I am feeling a bit lonely. Seriously. Great. Headphones.
And now, without further ado, I present... a silly number of pictures: