Ask HN: How do you organize files on your computer?

Currently I just have folders for high level topics like Media, Finance, Projects, etc. It works, but as I accumulate more and more files every year, I am finding my current nested folder structure sub-optimal. Some examples of problems I run into:

* Finding files becomes difficult

* Confusion when there is ambiguity: e.g. does my eye doctor's receipt belong under Receipts or Health?

* Having other family member's files also on the same computer.

I was curious how other people go about it. Is there some organization system you use? Is there some software that can make this easier?

Thanks.