You can legitimately do this with brass instruments, I don't know about woodwinds. You puff up your cheeks and use them as a source of air kind of like the bag on a bagpipes ('bagpipes' is singular I decided) while you sniff a breath through your nose. You can sustain a note until you get bored. Don't know if you can puff out your cheeks with the mouth shape you need to play a flute.