In particular, for this review, an Anet A8. If you’re willing to add a little sweat equity and fix up some of the bugs, an A8 can be turned into a good 3D printer on a shoestring budget.
With a bit of work, you may also have a PCB miller. That’s the basis of this neat hack by [Gosse Adema], who converted an Anet A8 3D printer into a PCB miller by building a holder for a Dremel ...