Life can have its little irritations when you're cruising around the world on your £100million superyacht. For example, the endless vista of clear blue sea fails to provide much greenery to ease the eye - apart from the odd tropical island. For the owner of a forthcoming craft named WallyIsland, however, this will not be a problem. For he, or she, will have a personal ocean-going garden. The 325ft-long yacht is to feature a growing area with shrubbery and flower beds, kept healthy by an irrigation system. It will also have a tennis court, pool and five accommodation decks including...