Bike innertubes are awesome! I use them quite a bit with my various edged tool pursuits. my first use was in the early 90s shortly after acquiring my Buck 188. I had read that someone used a strip from a bike innertube to fatten the handle and lend more grip. I had recently replaced a tube in my road bike at the time, so I decided to try it. Worked like a charm!
On the 188 I used a section of a whole tube. these days I buy mountain bike tubes and cut them lengthwise into strips about 3/4" thick. I use them for improving hand/handle relations on knives (CS Bushman is an excellent candidate), but mostly to affix fire starting gear to sheaths. You can get 3-4 strips out of one tube. I buy the cheapest tubes I can find.
Buck 188. Still has original tube, shich is still stretchy and tacky:
Various tools with fire starting gear:
The tube strips, as mentioned by others, have all sorts of other uses, too. Spinting fractures, tourniquet (temporary, for field IV starts), binding/securing wound dressings, attaching things to packs, leg straps sheaths/holsters/pouches, etc, etc, etc...