One of the most common top and bottom sets are called fullers.  The term "fuller" comes from the cloth making industry where round ended beaters are used on cloth to loosen thread fibers. This made the cloth softer and "fuller". The process probably predates metal working by thousands of years.  In smithing a fuller is a tool with a round or parabolic "nose" that is driven into the hot metal.

Then there is the round swage.  Round swages are for making a round area truer after the initial forging process.  Commonly used in the mortise and tenon process of joinery, but can be useful for many other processes

Flatters are also common in this category.  As the name says its for flattening.  Commonly used in knife-making to get and area of the blade flat. Often used to make and offset more precise and even and squareing of the corner of that offset.  

**Since hardy holes are traditionally not exact some fine tuning of the tool maybe required**

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