Maybe there’s another tool I’m not thinking of, so be sure to let me know in the comments if I missed it. As for me, I have a manual mill, CNC router, and recently, a manual lathe. They were obtained in that order, but if I had to choose one, it would probably be the CNC router.
The manual milling machine would be hard to give up though, as it’s incredibly useful for doing stuff that I need to take a small cut off of, or for use as a really great drill press. My CNC router from Zen Toolworks is capable of doing more detailed stuff, including PCBs if needed. In theory, once something is designed it can be set up and run, but there is a learning curve associated with it that shouldn’t be overlooked. It’s now more of a tool for me than an experiment (which is great), but that’s after over a year of work. I’ve documented this in my CNC catgory, so check it if you want – there are 14 pages of posts as of this writing! Or take a look at this post that shows the ZTW 7×12 going together.
My lathe will also be a really cool addition to the shop, but for what I’m doing it will most likely be used less than my CNC router or milling machine. Anything circular though, and a lathe is a great tool to have. It’s very new to me, so I may find more uses for it than I now realize.