After last week’s launch of a $4bn gold-plated superyacht we look at other crazy craft that boat builders have in the pipeline.

This is “The History Supreme”. It’s the world’s most expensive yacht and a Somalian pirates wet dream, which was sold for over $4billion to a Malaysian businessman last week.  It’s covered in 100 tons of gold, has sleeping quarters covered in platinum and a statue made from the bone of a Tyrannosaurus. Oh and it floats.

Cash-wise that’ll take some beating, but we scoured the seven seas to bring you crazy concepts that have got rich Arabs and Russian billionaires rummaging for their chequebooks…

5) CITY SHIPPERS
Massive cruise ships are often dubbed floating cities, but the designers of “The Streets of Monaco” have taken that literally – planning to recreate large chunks of the playboys’ paradise on water. Expected to cost around $1.1 billion there will be miniatures of the famed Monte Carlo Casino, Hotel de Paris, Cafe de Paris and the Loews Hotel as well as swimming pools and tennis courts. But the best bit is the Monaco Grand Prix-inspired go-kart track complete with tunnel complex that runs around the deck. Careful, though. One wrong turn and you’re shark food…

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