What really impressed me is the beauty of rural Japan. I have visited many places that a normal tourist wouldn't have travelled. Also tour operators will not take you over to these places as well. You need to hire a self-drive vehicle and it takes a fair bit of time. When you travel you need not only waste time looking at concrete structures. Beauty lies far away from the cities.
What really impressed my son was probably the Toilet seats. I guess the first time he went over there he spent about 30 mins fiddling with all the buttons to figure out the technology.

Apart from that he loved the Toyota Factory tour as boys are interested in cars.
One more thing that impressed me was their
optics. While in Kyoto we visited a large store. They had a designer frames clearance sale. Unbelievable prices. My wife selected one and went to the counter. Fortunately the young boy at the counter could speak fluent english. He was a Uni student studying Optometry. He said the price includes the lenses, with an adjustment on the type and features.
She normally gets her specs from Singapore whenever we pass through and quite expensive. She has varifocals with minor astigmatism correction and the two eyes are different. Usually expensive because she goes for the thinnest lenses to minimize the weight.
Anyway, she had a very recent prescription with her and handed it over to the guy. He said I just need to verify and asked her to sit at a machine. Within a minute the machine generated a report. Then he said this report doesn't match with the prescription she has and borrowed her existing specs and placed it in another machine. Then he said these glasses are also incorrect. Then he scanned her eyes once again and there was a similar report from the machine.
I said there's no time for us as we will be leaving Kyoto tomorrow. Then this guy said that all it takes to grind the lenses is 40 mins, plus further polishing and minor corrections if needed and come back in an hour. I saw him getting out two blocks of Hoya glass lenses, inserted them to a machine that grinds these.
After an hour went in and the specs was ready. With it her tension headaches also disappeared, because she wears it all day. Worth making a trip to Japan to get specs. That's really impressive optical technology.
I love to travel to Japan any day... even after having visited there a few times. I have many Japanese friends in there too.