That's cool. I never thought about cutting the funnel. Would it be pretty easy to cut the glass without breaking it? I've never tried cutting any glass before.
One idea I had was to just make something along the lines of this.
Sorry for the crude drawing, but I was just thinking of using some vinyl tubing again with some sort of cap on the end to hold the fluid in. Not sure if it would work out perfectly, but I was assuming that heating it, bending it, and cooling it would make it keep the "U" shape.