It is the biggest private yacht in existence and comes with a missile-detection system, two helipads, a luxury spa, swimming pool and a miniature submarine.
This is for Russian oligarch Roman Abramovich and only the most ostentatious displays of wealth will do.
His latest baby is the Eclipse, a 557-footer reported to have cost a staggering £300million.
As it glided out of the Blohm & Voss shipyard, in Hamburg, Germany, it was so breathtaking that many stopped to watch, barely able to believe their eyes.
To keep the oligarch safe, the Eclipse has a military-grade missile defence system, armour-plating around Abramovich's master suite and bullet-proof windows.
There is also a private submarine, which doubles as an escape pod.
The project has been shrouded in such secrecy that at one point the shipbuilders would only say that a yacht called Eclipse was being built somewhere in Germany. Needless to say, they would not confirm who had bought it.
There is little doubt that 40-year-old Abramovich who already owns four luxury vessels, is the proud owner.
According to industry experts, the Eclipse has been specifically designed to overshadow the world's current largest private yacht, a 525-footer owned by Sheikh Mohammed bin Rashid Al Maktoum, the ruler of Dubai.
Abramovich's new toy is due to be delivered in 2010 and will join the rest of his fleet. None of his ships  - the Pelorus (377ft), the Ecstasea ( 282ft) and the Sussurro (161ft) - are insubstantial but the Eclipse will dwarf them all.
The oil magnate, who is the 11th richest man in the world according to Forbes, uses his yachts for very specific purposes.
Originally built for a Saudi sheikh, the Pelorus is used for entertaining and boasts room for 22 guests and 40 staff. It has two helipads, an indoor pool and a steam room.
He uses the Ecstasea, which comes complete with Chinese-themed interior, for cruising and the Sussuro for short journeys and to loan to friends.
Annual overhead for the boats is more than £15million, and it costs him £73,000 just to fill up the tanks of his current largest boat, Pelorus.
The son of Jewish parents, Abramovich began his business career selling plastic ducks from a grim Moscow apartment but, within a few years, his vast wealth spread from oil conglomerates to pig farms.
Russia's richest man has flourished under president Vladimir Putin, with critics saying he used his government ties to take over former state-owned assests and reap the profits for personal use.
Outside of Russia, the 41-year-old is known as owner of the Chelsea Football Club. He is also known to entertain players and British financiers on his yachts.
Abramovich reportedly lost up to £13billion in the global financial crisis, but he was already in the process of having his biggest-ever yacht built.