Zwinktopia (http://www.zwinktopia.com)

Parents need to know that although you have to be at least 13 to sign up on this popular social networking site, it's not appropriate for young teens. As they roam around the virtual world of Zwinktopia, kids can pick a place to go and chat with other avatars (or Zwinkies). Filters automatically replace bad words with "(bleep)," but there are ways around it -- typing "fu" instead of "f--k you" or "ssseeexy" instead of "sexy," for example. People can be harsh and say mean things or just simply walk away. They can also divulge personal information (age, location, MySpace page, e-mail address) in a matter of minutes. Teens are encouraged to earn ZBucks -- or use real-world cash -- to go shopping for their avatars. When they're not chatting, kids can also play harmless games that actually require a bit of concentration and hand-eye coordination in order to earn ZBucks -- a form of currency needed to buy your avatar new things.