I carry vasaline soaked cottonballs in my pack. They are supposed to be excellent fire starters. I haven't tried them though. I should probably give them a shot BEFORE I actually NEED them. I also carry a small amount of cloths line rope and a space blanket in my pack just in case.
Ya stuffing things in your pack that you think will work isn't the best idea.
I've seen the cotton ball method in uses and I think it is a poor choice considering all the other options.
You can get a brick of magnesium and a striker for around $4.00 online.
tampons work Awesome for getting fuel from your tank.
A 9v battery and some steel wool is also a great source and very light weight
Just a few options I've used with great success.