Question:
Traditionally I know you should not dent them so what kind of furniture would you put in there?
Just curious now :3
Answer:
Carefully :p
Basically, you're going to want stuff that isn't going to rip up the tatami. Traditional Japanese furniture like light-weight tables and Japanese-style futons are designed for use with this type of floor. That said, you can use other kinds of furniture as well. For example, in my apartment I had a large wardrobe in the only tatami room (my bedroom). I noticed that it didn't leave dents in the mats when I had to move it from my old apartment to the new one, and it seems to be fine on the mats as long as I didn't move it around much.
That said, there are some things I would recommend never using on tatami mats, like rolling desk chairs. The person who lived in my old apartment before me got a rolling desk chair and put it in the tatami room. There was a giant hole torn in the mat from him using the chair even before I moved in, so when I moved to my new apartment I made sure to put the desk and its chair in a non-tatami room. Technically speaking you are also suppose to avoid all footwear (including slippers) in tatami rooms and to go barefoot or in socks.
