I bought a Mora 840G knife from Bushcraft Outfitters, and really love the knife. But the plastic sheath leaves a bit to be desired. For one thing the knife can fall out of it pretty easily. And the sheath can be knocked off your belt. I wanted to fix both those problems, but being too lazy to make a real leather sheath, I decided to see what I could do with the plastic sheath.
I drilled 4 holes in the sheath and ran some paracord thru them, added a plastic bead that I had, and voila! here it is. It can be carried as a "dangler" using the paracord loop, or it can still be clipped onto a belt if I want. When it's dangling, I loosen the bead with my right hand, reach around behind myself and hold the sheath with my left hand, and remove the knife with my right hand. Now I won't lose my excellent knife.