I happened to be listening to the Scottish traditional singer Belle Stewart's performance of "Queen Among the Heather" when I opened this thread:

http://www.tobarandualchais.co.uk/en/fullrecord/13040/8

I've got the tune in my Nine Note Tune Book, but ABC can't come near notating what she does with it. An ocarina can reproduce those extraordinary swoops and slides, as ubizmo says. No flute or whistle player would ever try anything that extreme. Here's Paolo Gavelli on the ocarina doing something like Stewart, in a "doina" (slow listening tune from Jewish Romania):

http://www.youtube.com/watch?v=7juxPQDqZHs

Not exactly beginner material, either of them.