502bhp Ferrari speedboat for sale

The world famous Arno XI Ferrari speedboat is coming up for auction in May, and you might want to begin pawning off many valuables in preparation. It's estimated to sell for around £1.2m.

Hosted by RM Auctions' biennial Monaco shindig, this unique racing boat is an intriguing and ludicrously cool sea chariot, built by Achille Castoldi in the early 1950s.

Signor Castoldi apparently wanted to establish a world water speed record, so invited his friends - Ferrari racing drivers Alberto Ascari and Luigi Villoresi - to convince Enzo Ferrari to provide "technical assistance". The old man agreed, and gave Castoldi a 4.5-litre, V12 Ferrari engine; a V12 like the one installed in the Type 375 GP car that gave Ferrari its first ever victory at Silverstone in 1951.

Castoldi took the engine, strapped on two superchargers and ended up with a 502bhp speedboat, which he used to hit a 150.19mph top speed in October 1953 on Lake Iseo. That earned him a world speed record for an 800kg boat - 800 kilos - that still stands today.

From there, Arno XI was sold and later raced in numerous competitions, finally retiring in 1960. It has since been restored and is expected to go for up to €1.5m.

An amazing story, but it does raise a curious irony. Because should you heed the concerns of leading environmentalists, it is the V12 and others of its ilk that are fuelling the earth's headfirst nosedive into a hostile climate of increasing temperatures and rising sea levels; sea levels threatening to wipe out many towns and cities and thus, forcing human beings to travel by boat.

A V12-engined, 150mph Ferrari speedboat, perhaps?

Click through for more pics, and click here to view another lightly astonishing auction next month. There are Porsches. Many Porsches.