Creating Voronois is difficult, beyond my capabilities anyway.
Luckily this clever sausage, Maklabu, has created the Voronator!
This tool is a simple web app, upload your stl and it gets voronated.
Concerned about what happens to the file:
“Storage of User Files and generated Data
All submitted files or inputs, as well as the converted outputs, are deleted automatically after half an hour. No backups are made and only employees of Maklabu GmbH are able to access your files. The files are kept for thirty minutes with the sole purpose of giving you enough time to download them. We do not look at them or mine any data from them.”