I finally made the tool that I've wanted forever: specify a couple of diameters, lengths, and bends and get a quick, exportable STL/3MF of my design in seconds rather than minutes/hours.
My personal use case was connecting vacuum hoses together in my workshop.
You can make practical designs: https://mankyd.github.io/pipefitter/#s=12~2~26|26.5~2.5~26&b...
Silly designs: https://mankyd.github.io/pipefitter/#s=12~2~11|12~2~112|12~2...
or outrageous ones: https://mankyd.github.io/pipefitter/#s=12~2~19|27.5~4.6~32|7...
And because all the parameters are in the url, its easy to bookmark and share whatever you find interesting.
I hope you find it useful, or at least interesting and fun.
Source code at https://github.com/mankyd/pipefitter