Instantly ideas spring to mind for literacy for this site Fotobabble. Another great link from the Web 2.0 in Education blog which would be very useful for many things in the classroom. It is somewhere in between voicethread and vocaroo as it allows you to upload a photo but not more than one. So it appears to me that it would be useful for children to use a self-reflection tool that could be embedded into their ePortfolio. There could be a photo of their work or of them creating their piece of work combined with their thoughts - challenges, triumphs, next steps. Whereas with voicethread the teacher would also be able to comment this would not be possible with fotobabbly, however, the comments could be added via post comments in a blog etc.
I think the part that would be appealing to many of my colleagues is the ease with which the embed code can be obtained and then the fotobabble can be transferred into a class blog/ePortfolio etc which is sometimes the tricky part for people to manage.