I remember that when L came out i'd dream of Last Angel, it happened like three times i guess, i was alone in my dream and randomly started to sing the beginning of the song.
Also I once dreamed that I was home at like 6am and knew some weird old lady was coming to kill me, so I was calmly packing my things to get out of town and I told myself with a smile "Let's leave this city before the sun rises" (And Then lyrics)
I dreamed of attending some concerts too, but i don't think i ever dreamed about a new song though