Small Forest Axe. The smaller axes/hatchets are handy, but the small FA does a lot more work in a lot less time, and I never notice the difference on a pack-certainly not in the toolbox.
The Scandinavian Forest Axe is really my "favorite", but I don't think I've actually used it more than once or twice. I made the edge a little steeper on the small, so it could handle more abuse, and end up grabbing it every time.
The Scandinavian doesn't do much except shave an occasional hair, and chop a piece of paper cleanly in half every now and then when I show it to someone.
One of these days I'm going to get one of GB's splitting mauls...