Nose flutes has been around forever here, played by the Ifugaos (a tribe of aborigines in the northern part of Luzon).
I've got a Muslim version of the mouth bow -- it's made entirely of wood and has a mellow, twangy sound. I bought it in this shop that specializes in ethnic instruments, mostly drums (made with lizard skin!), rainsticks, some of those shakey eggs, and something that sounds like the sheep-herding tambourine mentioned earlier.
If anyone ever drops by this part of the world, I'll bring you to the shop -- I've heard there's this group that uses those instruments and plays in local nightclubs...
sla/n cleod