I tried the mouse pad and sandpaper approach sharpening my knives some time ago. Since it has worked great for me, I wanted a slim mobile solution I could bring with me in the backpack. 
So I took a rectangular piece of wood, rounded off a part for handle and then glued strips of mouse pads on 3 sides and a piece of leather on the 4th side.
Then I added some screws so its easy to attach and remove the strips of sandpaper. I have so far used 220, 400 and 1000 grit. Then I use something called Autosol Metal Polish. I apply it on the leather and let it try before I give the edge a final workout. Works great! :thumbup:
But pictures say more than words:
Boar-gen
So I took a rectangular piece of wood, rounded off a part for handle and then glued strips of mouse pads on 3 sides and a piece of leather on the 4th side.
Then I added some screws so its easy to attach and remove the strips of sandpaper. I have so far used 220, 400 and 1000 grit. Then I use something called Autosol Metal Polish. I apply it on the leather and let it try before I give the edge a final workout. Works great! :thumbup:
But pictures say more than words:
Boar-gen