I've settled on a combination of a Lansky Puck, Smith's Coarse/Fine 4" diamond stone, and a sharpening steel on everything from my axes and hatchets to kukri and field knives to the ones I use to skin and process deer to my EDC. I've used setups as fancy as a high end Tormek, and they work, but I can get 85-90% as good of edge much faster and cheaper with what I described above, and it is portable, powerless, and hassle-free.