A well/pump/drill combination that extracts water/oil from under the surface along with some sort of combustion engine generator and a refinery for fuel.
I loaded up an old world 0.38.0 into 0.38.1 and it feels as though oxygen and food are depleted faster than they used to. Not sure if this is intentional, a bug, or merely a part of my imagination. Just felt as though it needed documentation.