According to the voki page: http://www.voki.com/
Voki is a free service that allows you to create personalized speaking avatars and use them on your blog, profile, and in email messages.
Evaluation of the product:
I have made a simple animated avator. The system supports many different language, so I can type in Chinese. The system generates voice based on my input text. The graphics are attractive and I think this tool can be integrated to teaching materials for children or teenagers.