I've been a big fan of podcasts, especially those having to do with history. I've listened to a lot of them over the years from subject ranging from Ancient Byzantium to the history of the English Language. I want to offer you my favorites. The great thing about one podcast is that it usually leads you to another. If you don't see a topic that interests you on my lists, then check put the The Agora Podcast Network. It is a great resource for discovering new history blogs. I download the podcast from iTunes but most can be found at various other places on the web.
The Egyptian History Podcast is an excellent one. Dominic Perry is a New Zealand Egyptologist who present the history of Egypt in about half hour, easy to understand segments. This is a must for Egyptian history buffs.
The History of Rome Podcast. Mike Duncan is the man many other History of... podcasts reference as their inspiration. This podcast series is a long one that, I bleive, spanned about five years. His dry humor and excellent research make it a great listen. He also produces the Revolutions podcast.
12 Byzantine Rulers - My understanding is that Lars Brownwoth is the man who really kicked off the history podcasts. Another excellent podcast that offers a great deal of accessible history.
Rex Factor - Two British guys in a shed present and rank all the kings and queens of England. After giving background on the monarch, the monarch is ranked according to traits such as longevity and scandal. The British podcast has concluded but they are currently doing all the kings and queens of Scotland.
The History of England - David Crowther takes you through the history fo England with a touch of humor, some drama and a lot of fun facts.
The History of English -If you want to learn how English evolved and where our words come from then this is the podcast for you. Also, if you like hearing Anglo Saxon or Middle English spoken aloud, then this podcast is a real treat.