Virtual world: habbo.com
Style is hot at Habbo, where avatars traverse the three-dimensional cartoon city decked out in hip sunglasses, feather boas, or varsity jackets.
Emotional draw: Kids who crave independence dive into Habbo to rehearse their imminent transition into adulthood. They choose new hairstyles, create social bonds with other teens, and find, furnish, and live in their own virtual apartments. It's like training wheels for the real world.
Cool factor: In Habbo's online forums teens talk about what's on their minds, from trouble at school to a new crush. (The Habbo staff monitors the boards to curb inappropriate behavior.) A "tag" system lets users know where on the site to find popular discussion topics. There are also mini games -- goofy diversions like snowball fights and log-rolling contests -- that encourage group interaction among Habbo's several million members.
Real-life rules: Kids get their own e-mail accounts, and adult-controlled characters called guides serve as monitors in case visitors need help. While there's no monthly fee, buying clothes and participating in advanced virtual events -- like moving to a more sophisticated apartment -- require Habbo coins, which cost about 20 cents each.