If you've never heard of Poptropica, chances are you're a grownup. An inventive megasite for kids with a wholesome and slightly educational bent, it features quests, games and puzzles set on 20 themed islands, including Shrink Ray Island, Wild West Island and ones based on the Wimpy Kid and Peanuts franchises. As many as 10 million kids explore Poptropica each month, but the site also aims to please parents. The chat feature, for instance, doesn't permit free-form conversation. Instead, members can select questions to ask one another from a collection of family-friendly choices.