In recent years I've discovered the joys of listening to history podcasters. This consists of mostly amateur historians telling the story of those eras which interest them. All of this content is free and generally of a very high standard.
Most keep to a schedule of publishing a new episode weekly. Each episode is usually about 30 minutes long.
To try them out, I recommend picking an episode from the middle or end of a series - after they've settled on a narrative style. Then start from the beginning if the content appeals to you.
Here are the ones I listen to most:
The big daddy of the movement is Mike Duncan. He did an epic series of podcasts telling the History of Rome from the foundation of the republic to the fall of the western empire (in 180 episodes). He completed the story in 2012.
Nowadays, Mike is telling the story of various Revolutions. He has told the stories of the English Civil War (21 episodes) and the American Revolution (17 episodes) in considerable detail. Now he is in the middle of the French Revolution (31 episodes and counting).
The History of Byzantium by Robin Pierson continued the story from where Mick Duncan finished. He is up to the beginning of the eight century (after 67 episodes).
Rob Monaco's Podcast History of our World covers the history of all parts of the world. After 58 episodes he has reached classical antiquity.
Chris Stewart's History of China has reached the end of the Sixteen Kingdoms period in 439 AD (in 57 episodes).
Last but by no means least of the ancient history podcasts is Paul Vincent's Myths and History of Greece and Rome. After 86 episodes he is in the middle of the crisis of the third century. His work is also available as e-books on the Amazon kindle: Book 1 & Book 2.
For the modern era, I recommend the When Diplomacy Fails by Zack Twamley. He has covered many wars of the early modern period, the nineteenth century and the first world war (in 83 episodes).
Also Talking History: The Italian Unification 1790-1870 by brothers Benjamin and Adam. They have reached the aftermath of the revolutions of 1848 in 48 episodes.
Finally, I must mention Dan Carling's Hardcore History He has done 54 episodes about various periods. His podcasts are infrequent and very long (2-3 hours). The most recent episodes are available for free but the older ones require a small fee. I particularly liked his series of episodes about the Mongols called: Wrath of the Khans.
Links to these and other podcasts can be found here: History Podcasters.
"Share and Enjoy"