A 390-foot superyacht designed to run entirely on liquid hydrogen is poised to make waves at the upcoming Monaco Yacht Show — where it will be listed for sale with a whopping $645 million price tag.

It has been billed as 'the most extraordinary yacht ever built'. A 390ft (118.8m) vessel – rumoured to be owned by billionaire Bill Gates – boasts a basketball court, beach club–style infinity pool, ...