Do you remember the Tamagotchi craze of the 90's? How about Beanie Babies mania? Brace yourself for the next wave of children's playthings  -- virtual friends.

It started in 2005, with the introduction of Webkinz  -- plush toys with their own online virtual world online.

Today, kids can choose from a variety of web friends, including buddies from Club Penguin, Jelly Beanies, Barbie Girls, Nicktropolis and others. Today, toy stores have a hard time meeting the overwhelming demand for Webkinz toys. Club Penguin reported in August that it had more than 700,000 paid subscribers.

With all these virtual worlds popping up, your kid is bound to want to join one of them. But which is the best for your child? Are they safe? How much do they cost? Before you buy, check out our guide to web friends.

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