Pascal Vandenbulcke was the flautist for avant-garde jazz-rock band Dun, who released one amazing album, Eros (which is now sadly OOP).
Anyway, in the liner notes it says that at live shows he would play the gruyerophone.
Here's a description from said liner notes:
On stage, Pascal played a totally new and original instrument, the gruyèrophone, also known as swisscheesophone, which he used to describe to the audience as "a wind instrument belonging to the hunting horn family, with a tuba mouthpiece and a square-shaped bell into which small bits of swiss cheese are introduced. The technique is not unlike that of the bagpipe. When the player is tired of blowing the instrument, the small holes in the swiss cheese then burst, taking over from the performer and allowing him to catch his breath".