Mindmeister (Mind Mapping)
Youtube for your iPad
For those of use that use Chrome I highly suggest you go to the web store and search for BIODIGITAL HUMAN its free and easy to use!
University of Virginia's Introduction to Radiology: an online interactive tutorial
University of Washington's Musculoskeltal Radiology
Google Drive is great for working on group papers and presentations (you will need a gmail account, which I highly suggest!)