Percusion pipes go to
Tom Tom-Tommimg
and nip down to the photo 26 to see one actually in use.
Then there is always the old favorite, the Humstrum.
No picture but... Fix a lenght of string from one end to the other of a rulker such that it traps a bean tin/can underneath at righ angles. Push the tin to one end and wedge to stop it moving. Now play the string with a bow of some sort and out will issue a not very musical noise!!!
Can be heard on Tim Laycock's "Lydlinch Bells" CD.
Sorry, another Forest Tracks
plug.

Good luck