I'm a madman for demos of songs. I'm a huge fan of the late Nick Drake (a great singer/songwriter/guitarist as well as tragic figure). Had never heard that demo until yesterday. Literally, it's Nick and his guitar on his parent's home tape recorder. Totally unknown at that point. The song was later recorded on Nick's second record, with orchestration. The version above gave me chills for its purity.
Here's a Sunday morning demo I was playing non-stop after David Crosby's recent passing. Again, I'm always blown away by artists like Crosby who can lay down this kind of emotion without much accompaniment or embellishment.
In keeping with the first post (high skill levels), here's Springsteen's original keyboardist (NYC Serenade piano intro, Kitty's Back organ solo) playing guitar: