iTunesU is an area within Apple&'s online digital media store where educational institutions provide their own collection of audio and visual material (such as lectures, talks and interviews). The material can be downloaded free of charge.
The University of Oxford launched its own section in iTunesU in October 2008 and saw its one millionth download less than a year later. The Oxford collection contains well over 1,500 items with new material being added.
The Oxford material can also be accessed from http://podcasts.ox.ac.uk