Name: Jonikal
Value: $45 million*

Now named Sokar, the yacht formerly known as Jonikal is fit for a king, or in this case another member of the royal family. Princess Diana was famously photographed aboard the ship with her then-boyfriend Dodi Fayed, as the two sailed through Portofino, Italy. 

While at the time, the photographs of Diana dangling her legs off the edge of the ship were nothing too out of the ordinary, they are now remembered as some of the last pictures of the young princess, who passed away along with her boyfriend in a fatal car crash just a week later.