An online store selling recordings of the weird and offbeat, from Terence McKenna to John Lilly to Faustin Bray.
Freely downloadable recordings of remote viewing instruction.
An archive of recordings from the early days of phone phreaking- stuff like conversations recorded off of bridges, tone sequences, war stories, stuff like that.
An archive of recorded messages and error tones from United States telephony networks. Available for online listening or free download.
A group of dedicated gamers record some of their sessions of play and publish them as podcasts for the rest of us to listen to. If you're not sure if you'll like a game, or if you think you're not running something correctly, see if they've run a session or two of your game and see how they did it.
An archive of pirate radio broadcasts from the late 1990's at archive.org. You can download them for free or listen to them online. The quality of some of the recordings is kind of poor (it is pirate radio, after all) but occasionally you'll come across a gem in the rough.
Archive of shortwave radio recordings to download.