In reply to jethro kiernan:
Last Podcast On The Left - macabre, black humour, focusing on serial killers (many you will not have heard of) as well as other dark subjects
The Joe Rogan Experience - tonnes of interesting conversations and interviews with a wide range of people and topics - he does his absolute best to be a fair and even handed host and you do hear him update and inform his opinions over time
The Firn Line - Alpinism podcast - a relatively young podcast but very interesting
The Enormocast - surprised no-one's mentioned this one - a staple of climbing material podcasts - especially the interviews with Hayden Kennedy on chopping the bolts on the Compressor Route - lots of good interviews by Chris Kalous
Trail Runner Nation - all you need to know about the current state of Trail Running (mostly US but some Euro Stuff)
Jocko Willink - Ex Navy Seal and author of Extreme Ownership - good empowering stuff
That should keep you in plenty of good free material.