If you’re a fan of science-y stuff (even if you failed hard in most science classes like myself), you’ll love Probably Science. Comedians and scientists join hosts Matt Kirshen, Andy Wood, Jesse Case, and (in earlier episodes) Brooks Whelan to talk about science news each week. Because it’s been around since 2012, earlier episodes are not available through iTunes, but you can find them on their Libsyn page.
Showing a bit of bias here as I’m friends with one of the hosts, but definitely check out Paradox: The Time Travel Podcast. Co-authors Phil Hornshaw and Nick Hurwitch dissect the very convoluted timelines of our favorite time travel movies. As the art might lead you to believe, the guys have kicked off their new show by talking Back to the Future and its sequels.