This is really neat:

The MultiMachine is an accurate all-purpose machine tool that can be used as a metal or wood lathe, end mill, horizontal mill, drill press, wood or metal saw or sander, surface grinder and sheet metal “spinner”. It can be built by a semi-skilled mechanic using just common hand tools. For machine construction, electricity can be replaced with “elbow grease” and all the necessary material can come from discarded vehicle parts. It can be built in a closet size version or one that would weigh 4 or 5 tons.

What can it be used for in developing countries?

Building and repairing water and irrigation pumps and farm implements. Building steel-rolling-and-bending machines for making fuel efficient cook stoves and hundreds of other products.
Rebuilding vehicle parts.
Providing “hands on metalwork training on student-built MultiMachines that they take with them when they leave school.