Oops, answered in the old thread. But my answer is more appropriate here I think.

I'm using this one: http://www.ebay.com/itm/251813416755 in my knife's handle (see the 3D printing thread) with the pen shell removed. Ultra compact! This one http://www.ebay.com/itm/262137581988 is my pocket EDC. They are good enough for maintaining the edge as well as for fixing it if broken. It's essentially a diamond file which has much more uses than just a knife sharpener (especially the conic one). Some knife sharpening skills are strongly advised, it's not a self-guiding type.

If you browse eBay you can find them even cheaper.

I bought this one back in summer 2012. I'm thinking maybe one of these days I'll get around to actually using it.

http://www.amazon.com/gp/product/B000UVN...ailpage_o06_s00

For all the use I've made of mine, I could have gotten by significantly cheaper with one of those from eBay that Alex recommended. At the time I guess I was thinking I might need to sharpen a knife on the trail sometime. But I've never even remotely needed to do that. So I guess this sharpener is a high quality brass handled paperweight for me. But it's a nice paperweight. I keep it in my bug out bag. That bug out bag is a pretty nice paper weight in-and-of-itself too. Maybe I'll bug out someday (I'm still waiting for those zombies to show up!) But at least I can sharpen my knife while on the lam.

I did use mine actually "in the field" twice to work on knives, once I needed to precise cut some plastic sheeting but found the tip of my LM squirt too dull for a smooth job; another time I broke the very tip of my folder and spent some spare time filing out the new one (not that I was really needing it right away, but for an aesthetic reasons). But I can recall much more cases of using it as a metal and glass file.

I would add another recommendation for the Fällkniven DC3 or DC4. Either model works great as a combo stone. The diamond side is high quality and lasts a long time (low-cost diamond sharpeners tend to have a pretty short service life). The ceramic side is fine enough to give the edge that smooth, shaving sharp final polish.

I own a bunch of sharpening tools, stones, jigs and power tools (including a belt grinder) but I keep coming back to the DC3 all the time - it just works really well and it's so versatile it can be used on anything from a knife to an axe or machete.

My Gerber sharpener is still working great. I also picked up a little Rapala 2-stage sharpener, that's very similar to my Gerber one. They were both under $5 and work great for touch-ups in the field.

http://www.rapala.com/rapala/knives/knif...p-fine/SH2.html

I have got a ton of these (at least a half dozen or more):

http://www.midwayusa.com/product/886556/gerber-pocket-sharpener-ceramic



Never actually used one. I have no idea if they work well or not. I add them to my orders from Midway because they are one of the cheapests item they have with free shipping. So when I add one to my regular order that normally would have, say, $15 shipping charge, the addition of this item lowers the overall shipping charge to something like $5. So I save $10 by adding a $2.99 item, for a net savings of $7. Can't beat that. I'll bet Midway is wondering why I order so many knife sharpeners! They're all sitting in my man-cave, still in their packaging. I could probably return them for a refund to increase my savings, but that would be unethical in my mind, so I just keep them. I guess I could use them for stocking stuffers at Christmas (but I think everyone in my family already has a handful of 'em!)

The ceramic side is good for maintaining an edge, but the carbide side will take a lot of steel off of you knife.

Both sides are ceramic
both are fixed at 18 degrees per side or 36 degrees inclusive

For the same price or cheaper you can buy a sharpening stone at your local asian grocery store

if you use too much pressure, it wears one or both rods, which then produces a horribly shaped edge, if it can produce one at all. so use it for touching-up, not for a making an edge on a very dull blade.

Actually no, those are small diamond rods, one pair coarse and one pair fine.

I have one of those Gerber pocket sharpeners, it's ok for what it is but I don't use it much. It only really works for smaller, thinner blades sharpened with a secondary bevel. Like Montanero said, the coarse side is too coarse and removes material too quickly, so it's a bit difficult to control. The fine side isn't all that fine either, less than ideal even for a quick touch up if you want a proper hair popping edge.

Also, Wileycoyote is right, the diamond rods wear our pretty quickly if any serious pressure is applied at sharpening. But realistically, that's to be expected from a $5 product.

Personally, I prefer a combo stone instead, followed by stropping on a leather belt with a polishing compound. You can get much better results with freehand sharpening. It's a skill well worth mastering IMHO. You can use a combo stone to sharpen just about any kind of blade, even an axe or machete. Fixed angle pocket sharpeners and jigs are not particularly versatile and don't work at all for scandi grinds, which could be a problem for many people.