A boat designer has unveiled plans for the ultimate purchase for privacy-hungry billionaires -  an 'invisible' superyacht which he says will appear to completely vanish into the sea.  The 106-metre Mirage, which could cost an estimated &pound;200 million, will be totally clad in specially mirrored glass.<br /> <br /> The panels, the yacht's designers say, will reflect the image of the sea back to onlookers, making it look as if the 4,200 tonne vessel has 'vanished' to people from as little as 50 metres distance.  As well as the ability to blend into its maritime surroundings, the craft comes fully equipped with a helipad, spa, outdoor theatre and cinema, and would be suitable for members of the world's super rich who value discretion.  SEE OUR COPY FOR DETAILS.<br /> <br /> &copy; Van Geest Design/Solent News &amp; Photo Agency<br /> UK +44 (0) 2380 458800
{}