iTunes

iTunes is a well known source for music from artists both new and old, but the site has much more to offer than just the newest singles. iTunes is one of the largest providers of podcasts, on topics like pop culture, entertainment, and especially education. The educational library of podcasts on iTunes is extensive and covers every topic from foreign language and English, to Math, Science, and Social Studies. 

As someone who listens to a lot of podcast I can attest to their educational value, and convenience as they can be taken anywhere and do not require the same kind of constant focus as a book, or long form web-lecture.

Finding the perfect podcast may be difficult, given the size of the library that iTunes has to offer, and I would never recommend presenting, or assigning a class to listen to one that you have not gone through critically before hand.

In the subject of history though I can give a few recommendations based off of the podcasts I have listened to: 

Revolutions recounts the history of the French and American, as well as Latin American Revolutions.

Hardcore History covers in immense and almost agonizing detail the history of WWI as well as other major historic events.

The Civil War Podcast, covers the US Civil War almost day by day, going over every detail, and explaining the battles and buildup to the war.

Using a podcast in the classroom may seem a bit unusual, however to my understanding it is no different than showing a film or video, and unlike film and video can easily be shared with the students through links (all three of the above are free to listen to).