You could have swappable parts that, say your hand attaches to (with, for example, a flexible grip by your hand). That way you could swap an enormous array of parts, using your hand as a universal adaptor.

Some of these parts could even by powered by your body so they don’t need an external power source. Like you could design a machine which, when attached to you by your hand, and powered by the rotation of your arm, could twist screws into the wall!