First of all, I include a song that was partially dream-composed by my mother; this ability must be inheritable. She had music and lyrics for the single line "in the middle of the night I saw you standing there in the middle of the night upon a thoroughfare" and I wrote the rest of the song around it. In the Middle of the Night
Second, here's one I wrote in college based on a dream set at Hickman High. I used to spend my lunch hours in the band room playing around on the piano, and in this dream, Joe Newberry was singing this song and accompanying himself on the piano. For the last verse, he opened up the piano and grabbed the strings to make the accompaniment more dramatic. The Open Gifts
Third, here's the other one from my college years. I was looking up musical terms in the library for a daily feature I was putting on the Phi Mu Alpha bulletin board, and the term "proslambanomenos" worked its way into my subconscious mind. I woke up with this tune running through my head, and at the end of every verse, a low voice sang what I thought was "proh-slam-bah-doh-mih-nome". I thought it sounded like a medical term, so I asked Arthur Freehand what it was. He didn't know, so I looked it up in the music dictionary, and there it was with the correct consonants for the last 3 syllables. Turns out it means "a low note". Freaky, huh? Proslambanomenos