Voki is a free service that allows your students to create personalized speaking avatars and embed them on a blog or wiki or send them via e-mail. This service provides numerous features to help students personalize their speaking avatar’s voice, appearance, hair color, background, clothing, and more. Additionally, when you make changes to your Voki these are automatically updated. These various options make Voki ideal for engaging students in any subject at any grade level.
http://www.freetech4teachers.com/2010/02/engaging-students-with-voki.html
Voki website: http://www.voki.com