I love the way emails are organized in GMail. I have long wanted something similar for my local files. The ability to have one file located under multiple hierarchies is a great advantage, and links are not a clean solution.
It seems that there are a variety of solutions for Windows, but I am not a Windows user where given the choice. Also, I found this blog post, but the link there is dead, and I'm always hesitant to use solutions from 4½ years ago without looking for newer ones, and I've not been a huge fan of Tracker. Also, there is this very clever solution, but I want to use this with more than media files—with all files in my home directory, if possible.
Is there a file manager for Linux (or even a file system format) that supports this? I'm willing to try something that is buggy.