From the first time my brother’s transistor radio rocked our Wisconsin farmhouse with a late-night, Top 40 broadcast from WLS in Chicago, I understood the world-expanding power of sound. More than 40 years later, I still open my ears to broaden my horizons, but now the medium is spoken-word podcasts.

I began downloading them a few years ago to catch up on NPR favorites — Terry Gross’ Fresh Air interviews, Wait, Wait, Don’t Tell Me’s news quizzes, Garrison Keillor’s Prairie Home Companion monologues — I had missed on-air. I still do that, and I still listen to WLRN in the kitchen and car, but thanks to iTunes’ “Listeners also subscribed to” cues, I’ve pieced together a crazy quilt of entertaining, edifying, sometimes oddball podcasts.

I listen to them on morning walks, workouts and swims (with a waterproof iPod case and ear buds), while trimming hedges or ironing clothes — anytime I need diversion from a mostly mindless task. And at the end of the day, when I’m too tired to read, there’s something soothing and almost hypnotic about listening to a podcast while playing Solitaire on my iPad.

The golden age of radio may have ended 70 years ago, but audio entertainment seems made for the mobile, multitasking 21st century. You can take podcasts with you almost anywhere and listen to them when you want — the audio equivalent of the television time-shifting that DVR players allow.

And did I mention they’re free? At least the ones I download are. The same “information wants to be free” ethos that is undermining the newspaper business has moved thousands of podcast producers to post their work online gratis.

Here’s a sampling of the podcasts I regularly download. It goes without saying that they reflect my particular tastes and barely scratch the surface of what’s out there, but I’d be surprised if at least one of them doesn’t pique your interest.

Fun and games

•  The Bugle: Hosted by “Daily Show” regular John Oliver and, from London, British comic Andy Zaltzman, this “audio newspaper for a visual world” offers smart, salty, often hilarious commentary on the week’s events. A friend was put off by their penchant for laughing at their own jokes, but I’m usually laughing along with them.

•  Ask Me Another: This hip, nerdy quiz show is noteworthy for the clever questions, the terrific song parodies and the face-saving good cheer with which host Ophira Eisenberg ushers off losing contestants.

Ideas

•  TED Radio Hour: Host Alison Stewart uses interviews to amplify “ideas worth spreading” from TED Talks, speeches by leading thinkers presented at a renowned series of global conferences. Recent topics: “Our Buggy Brains,” “The Future of Cities,” “Where Ideas Come From.” (The talks themselves are also available for download.)

•  In Our Time: Hosted by Melvyn Bragg and produced by BBC Radio 4, this weekly show brings together scholars from British universities for erudite, often lively discussions of “the history of ideas.” Recent topics: James Joyce’s “Ulysses,” game theory, Prussian military thinker Carl von Clausewitz’s seminal treatise “On War.”

History