I've never really understood why one has to bury or cremate a body in a box anyway. Carry it into the church or crem in one, sure, just for ease of transportation, but as Sammmo suggests, make it re-useable. Bring back winding sheets or shrouds as well and then there's no problem with squeamish people seeing dead bodies at the commital. Normal coffins give off huge amounts of toxins when burnt (so I am told), so they obviously also leave behind traces in the ground, which has to be bad for the environment.