Baubles is a small addon mod and api that is intended to be used by other mods to add additional inventory slots to a character.
It adds 7 new slots: an amulet, belt, head, body, charm and two rings slots. The baubles inventory is accessed by pressing the 'b' hotkey. It is probably a good idea to remap your normal inventory hotkey to the baubles inventory if you are going to be accessing it a lot.
This mod adds very little content itself - it is intended to be an addon for other mods and the only reason I included an item at all was to serve as an example for other developers. The Miners Ring has no crafting recipe and is only attainable in creative mode.
More information and developer versions can be found on the main thread