eBackpack offers storage and collaboration features to individuals, classes, teachers, and schools. Now, there is an iPad module to help manage workflow and student portfolios. The pricing is quite affordable.
3DTOAD.com is a library of 3D images that you can rotate and explore. It includes skulls, skeletons, dissections, coral, geology, and even music. These could be great visuals on an Interactive White Board or used on an iPad.