Cayo Espanto (Belize):
One of the more famous privately owned resort islands, a stay at Cayo Espanto will only run you about $2,000 a night, and has been a key destination for a laundry-list of high-profile Hollywood celebs. It also served as Leonardo DiCaprio’s inspiration for Blackadore Cay (and he even partnered with owner Jeff Graham to draw up the plans).