Kathy Schrock's ~ iPod touch online applications for education

Kathy Schrock has evaluated a number of tools that can be utilised with the iPod touch in an educational setting. Her blog post, iPod touch online applications for education lists and describes 18 online sites that could be uitlised with the iPod Touch. A number are straightforward sites such as "This Day In History" while others, such as Listingly, can allow for more practical uses of the iPod Touch. Can you suggest any others?