These days I have all my code in ~/code, a sub folder for each project. I've got apparently accumulated 120 project folders in the last 5 years. Anything else I make tends to be a loose file in ~/assets.
Whenever I get the urge to do some 3d modelling, I quickly check spotlight if I've started anything like it before. I get the urge to make a castle? cmd + space, type castle. Yup I last edited castleTown.blend in 2014. Then I just pick up where I left off.
My assets folder, being something I do to relax, has grown pretty ludicrous. It's distributed between a few devices, but i'd estimate I've got 2-5000 different made-from-scratch 3d models, digital paintings, textures, alpha maps, etc all over the place. Kinda wish I could have a garage sale from time to time :D
The only other kind of file accumulation goes in ~/Downloads, and I delete that wholesale every few weeks.
Thanks for making me reflect on my.. accretions..