Soccer cleats. They give me good grip on grass but dont lock me completely in so I can still move when I spin. I might make some hammer boots eventually, but in the meantime the cleats give me good lateral stability even then.

Some advice for anyone who plans on picking the caber in inclement weather - get cleats. Twice now, once on grass and once in mud I almost had my feet go out from under me while carrying the caber. Believe me, the last thing you want to see is a 16 foot long, 120 lb log falling down on top of you.