(Edit: It's not free anymore. I guess there's not much point to this thread anymore. Anyone with the power to do so, feel free to delete it.)

I just found out about this, and don't know how long it will be free, so if you're interested you probably should go grab it as soon as possible. It's a virtual Armenian whistle called a 'shvee'. I haven't had a chance to try it yet, but thought I'd share the link right away, before it's no longer free.

http://itunes.apple.com/us/app/ishvee-lt/id341982249?mt=8&ign-mpt=uo%3D4