A compound rest for the wood lathe can be very useful. As mentioned before my used Rockwell/Delta came with one but if they are still available, a new one is quite expensive. With a compound you can turn aluminum, brass and other softer metals on the wood lathe and if you can get your speed low enough even mild steel. Very useful for the hobbyist who would rather avoid the high cost of metal turning equipment.
This one looks solid enough to do light metal work. Switching out the hardwood base for easy to work, mild steel or aluminum, would allow for heavier more accurate work. This plan uses the "no castings" idea from J.V. Romig (the author) for the tool slides in this post Machine Tool Slides.
For straight or stepped wood turning the compound is safer and more accurate but has the limited range of action.
Here's something interesting that even MacGyver would be complimented for knowing. I wasn't aware of this method and I haven't done any research on it (I am not aware of any desalination plants based on this process). Nowadays a tight plastic snap lid and the clay pot is all you would need to survive two weeks in a rubber raft on the open ocean, lol.