The HotTug is a boat that you can sail after filling with up to 2000 liters of water heated by an onboard wood stove. Say again? Other than sailing, that boat has the main functionality of being almost fully submerged in water – and not sink. It is constructed from wood and fitted with glass fiber reinforced polyester, and holds a stainless steel wood stove to warm up the water.

It comes in one standard size that can fit 6 to 8 people, but can be purchased with or without the wood burning stove, and with or without the electric motor as it can also be powered by a standard outboard motor. Pricing ranges from $11575 (€8950) to $21300 (€16450).