If you enjoy absurd precision and accuracy, have a look at Dan Gelbart's older videos where he fabricobbles together a custom milling machine and grinder with air bearings that can work parts down to 1 micron. No lapping needed.
I like the idea at least of the late Dave Gingery's books: start with a home-made foundry, progress to a lathe.
I don't think I could suffer the janky gimcrack I would come up with though — I suspect even the bargain Harbor Freight lathes would put mine to shame.
I was amazed at the accuracy and surface finish he could achieve with homemade parts.