I just ran across this new product that is really very old - Bark Siding. It is made from bark that is harvested off of trees that are felled for other purposes. The bark is then flattened and kiln-dried and that's it. No preservative treatments or special coatings. You install the siding and leave it alone. See photos below.
The look is definitely on the rustic side, so it's probably not a great candidate for your urban infill projects. But it does look at home in a wooded setting, which might make it a good choice for your cabin plans.
The product is touted as being long lasting and sustainable, although I am always wary of manufacturer claims. You can check this out at the manufacturers website Bark House Siding
Anybody have any experience with bark siding? Please throw your two cents in.