There's so much you could do.
- have a reverse proxy for your services, as containers
- connect then through netbyrd or nebula if you want the FOSS route (or headacalescale)
- set up an IDPS, such as fail2ban, snort, etc
- Set up a backup job, there's many projects that does this well - check out Borg and kopia.
- since we're on linux, try out different shells. Zsh or fish are pretty popular and pretty to look at.
The car garages. I never drove a car in Japan, but it looked like there was a system and some kind of futuristic hydraulic automation thingy to put your car in an available slot??
But in general, I got a lot of retrofuturism vibes in Japan.
Also, while not technology, it is worth mentioning that people there are incredibly polite and friendly - even in Tokyo rush hour.