It's strange how things crop up. Not so long ago I was chatting with a friend around the fire and discussing how certain letters have been dropped from the English alphabet. Yesterday I watched an interesting video which talks about the same letters - link here
What we notice (and what isn't discussed in the video) is that most of these extra letters evolved from the Anglo Saxon runes or took their runic names.
So here some the letters which we've dropped from the alphabet - and their runic origins.
þ - thorn - ᚦ - Thorn / þurisaz
ð - eth - as in Eðel / Ethel
æ - ash - Asc or Ash
Ƿ - wynn - ᚹ - wyn / wunjo