The living bridges were new to me. I like the concept, would probably also work in more cold areas, but with more effort.

https://en.wikipedia.org/wiki/Living_root_bridge

Holy cow this is so cool <3

One of my favourite examples is bonchi, or bonsai chili. It's exactly what the name implies. Unfortunately I've struggled to keep a regular pepper plant alive, let alone bonsai it:

https://old.reddit.com/r/Bonchi/top/