There are a lot of materials, which works as a tinder in fire making. In Finnish traditions the most common and most used tinder has always made from Fomes fomentarius, also known as a "false tinder fungus or hoof fungus. This is the same material the well known "iceman otzi" had in his bag too.
Tinder made from Fomes fomentarius is well known also among Finnish woodlore-hobbyist and bushcrafters even today. For example the "trend" of making tinder from cotton fabric has come to Finland from USA and U.K. and it´s used more among "new age"-bushcrafters.
In Finland we have a wide traditions about woodlore and many techniques and knowledge about living straight from the nature are still known very good.
We are people from cold and dark north and the forest is still our home. =)
I made a little video about making tinder in traditional way. Many people have asked me to make this video and I´ll be grateful, if even one person will find this video useful.