Back in the 60s there were a couple of guys in one of the Guards regiments who got in the papers and on the telly by playing their rifles. They still had Lee-Enfield .303s in those days; you opened the breech, shoved a bugle mouthpiece into the muzzle and ... just played! Didn't sound too good, but as Dr Johnsosn said about the dog walking on its hind legs ...

I also remember James Robertson Justice (I thik!) playing a tune on his hand in a similar manner: he made an "OK" sign with his thumb and forefinger, and blew through that!

Steve