Joe wrote:
"-ly forms adverbs from adjectives.  I suppose the correct way to make an adverb there would be 'hammerfully'.."
Well, if English were less idiomatic, 'with' wouldn't have the countless meanings it currently has... And I wouldn't assign '-fully' to all its meanings. Not unless you were trying to immitate Tzeltal somehow, with its single preposition <ta> :) ... You might have: 'man gunfully', 'went to the movies herfully', 'boy brown hairfully' etc. :)