I wanted to make a long horn, which involved bending itself up and down a few times to make it more compact and playable. The areas where the pipe doubles back upon itself use an interesting solution for making the necessary bends. There is undoubtedly more turbulence in the bends of this instrument than there is in the smooth bends of professional instruments. It only costs a couple dollars to make, though, and it is so much fun to play that I'm willing to cut it a little slack in my critique.
The use of rubber bands in combination with clothespins is also an interesting technique for holding the rolled up plastic while gluing it all together with silicone rubber. They make adjustable, elastic clamps. They would undoubtedly come in handy for other projects, and maybe deserve an instructable of their own -- simple but effective holding devices.
Silicone rubber makes an excellent glue for this material. I use hypodermic syringes with plastic tips for precise application of the silicone.
Be sure to hear the audio sample of the jumbo sax tootophone in the last step.