#5 better not be the only person I can think of, because I wouldn't call him bluegrass.

#10 - the Dillards, or Doug Dillard, but I can't remember the original title. Something about a banjo and guitar? Certainly not "variations on Yankee Doodle" which is what it is. I remember hearing them play it on an Andy Griffith show rerun, telling people and having them reply "You couldn't have heard it, it's too new."