What's the name of the board game about sailing between islands?
Tongiaki, perhaps?  Description and image à la BoardGameGeek:


  This game uses a unique tile design never seen in any other game (hexes with wavy edges), and is easy to explain and easy to enjoy. Players all begin on the island of Tonga, and immediate overcrowding forces players to search out other islands to populate. For each expedition that leaves, a new tile is placed, revealing either an island, or a "water path" that may or may not have a number from 2-4, indicating that many different players (not number of boats) must make up that expedition for it to survive the voyage (draw and place an additional tile). In this way, the game encourages both cooperative and competitive play at the same time.