It’s becoming impossible to keep up with all of the great ones out there (right now there’s more than 40 podcasts to listen in my Instacast), but here’s my narrow selection.

Web development:

• Shop Talk Show - About front-end web development & design, featuring awesome guests, with questions from listeners.
• RailsCasts

Education & Comedy:

• Radiolab (up to 60 min) - “Science meets culture” in a form of stories, investigations, and experiences.
• 60-Second Science (1 min) - Daily commentary on some of the interesting news in the world of science.
• The Moth or “True stories told live” (~ 20 min)
• a show with zefrank (~ 3 min)
• Savage Lovecast (~ 50 min) - Advice columnist Dan Savage answers questions about sex and relationships. Insightful, provocative, and funny.

Language:

• Learn French with daily podcasts (~ 5 min) - Useful to stay in touch with your existing (beginner to intermediate) French, and expand your vocabulary. Funny accent included. (Louis is adorable.)
• Grammar Girl Quick and Dirty Tips (5–10 min) - English grammar, punctuation, and style.
• Lexicon Valley (20–30 min) - Simply about language.

I only recently discovered The Art of Photography and really like it. I also occasionally listen to Big Ideas, Ruby Freelancers, and Back to Work.