Jon Rose is an Australian violinist/artist/composer who has done many cool things. here (QT link) is a clip of him playing barbed wire with a violin bow: "One aspect of the barbed wire fence that appeals to me is that it becomes very clear where the notes are - if you miss'em it's quite painful. Also the scale articulated by the barbs is extremely unorthodox and about as far as you can get from the equal tempered scale upon which most western music is played. But the tyranny of the equal tempered scale is not a subject upon which we should dwell in the middle of an Australian desert.".
And here he is conducting an orchestra made up of violinists, a drummer, a pianist and several chainsaw players. There's a lot more interesting stuff, including a MIDI bow being demonstrated on daytime TV, at this page. (Thanks Sam)