I just got a "low" G whistle. It's got a really cool sound. I think I'll be working out some airs for it. It's cool, because I can play highland pipe tunes on it in the proper key, with the low-g (albeit with different fingering.)

Here's a really cool slow tune that I play. It's called Eily Gheal Chiun
http://www.youtube.com/watch?v=XVVDUj6B8pg

My friend, who plays harp, taught it to me. He takes lessons from the two in the video. We play it in F (I use a Generation Bb), and I suppose that's what's in the video.