have you seen the latest limited edition of Montblanc's fountain pen ? It's a tribute to Leonardo Da Vinci. And honestly, it's full of details that could also serve the watch purpose !
See the red gold plated gear at the end of the clip ?
The Montblanc Great Characters Limited Edition Leonardo consists of 3000 fountain pens and 3000 roller ball pens.
Price : 2800 euros / 3800 USD.
Worth it ? Your opinion ?