Cold Steel manufacturs a number of tomahawks, and there are ample courses, videos, and books out there on their employment as a defensive weapon. They can be fearsome in the hands of someone who knows how to weild them, and the rest of the time, pack away neatly as "camping equipment."
This summer I took a very large truck bearing race and hammer forged it into a fighting knife, some of the well known knife makers use bearing steel, Cold Steel has some really nice shortened versions of a Katana, pricey as all getouts and these have been supplied to “special forces”.