Antonio Stradivari created violins that are renowned for being the best. A while back I looked up 'stradivarius guitar' on a whim and was pleased to find this video on Vimeo:
The sound of an original Stradivarius guitar: The Sabionari (1679) from Roberto Domenichini on Vimeo.
I can't believe an instrument form 1679 is still intact, let alone sound like that! It sounds more like a lute — and maybe is strung like one, as I'm only seeing 4 doubled-strings, I think?
You can read more about this remarkable instrument at sabionari.com.