My daughter (and wife) seem to be hooked on the second grade version of Second Life called Webkinz. With Webkinz the cost of entry is the purchase of a physical stuffed animal that is bundled with a unique code that allows you to go online and virtually care for your pet. You can create a house for your pet, complete with bedrooms, bathrooms, kitchens and a trampoline in the back yard. You then engage in lots of virtual activities like taking baths, making food, playing games and working (you can only work one job every 8 hours, perhaps so they stay compliant with child labor laws – kidding).
You can also engage in limited interaction with other Webkinz, though it seems to be closely controlled (perhaps to prevent child exploitation). This game appears to be as addictive as its elder kin such as Second Life and World of Warcraft and represents the first time I’ve had to institute a Bill Gatesian limit on my daughter’s screen time.
There is no charge to play Webkinz, but when your account expires, you MUST buy a new stuffed animal to stay in world. An interesting recurring revenue model. I can only assume that they intend to be able to keep up with the recurring demand.