I remember a clip of Siobhan Ní Chonorain whistling that appeared on 'Come West along the Road' at some point. It may be on one of the DVDs.

You do come across this sort of stuff occasionally: when Dympna O'Sullivan launches her first recording she had a Mayo man (John O'Donnell?, can't really remember the name) on the launch night who was pretty brilliant.

I have some (non commercial) recordings of different people whistling. It's usually good fun but I can take only so much of it.