I've listened to a few podcasts now, so here's my opinion on a few of the techy-oriented ones. Note: most of these can sometimes/often contain language or even songs you might not want your granny to hear (except the Palm ones and ReelReviews, you're pretty safe there).
- PalmForums - own a handy rss feed, but for the podcast - dull, boring voice. Try the usually bite-sized PalmAddicts instead - at least a bit more interesting.
- Daily Source Code - he can be an arse, but he is the 'PodFather' and if you want to keep up with what's happening in the podcasting world - especially on how it's meeting the real-world media - it's worth keeping an eye on Adam Curry's 'cast (or at least his rss feed). Hard work to keep up though now it's regularly daily (as I mentioned recently)
- Dawn and Drew - funny, risque, rude, crass, downright distasteful at times; but more than enjoyable. The best and funniest 'cast about nothing-in-particular that I know of. Now daily.
- Reel Reviews - the best movie reviews podcast I've come across, particularly for pointing out older classics you might not have seen yet.
- LUG Radio - the most entertaining Linux podcast around and with enough clout to get interview time with big cheeses of various important sizes from the big companies/organisations in Linux (Novell, KDE, IBM GNU to name a few), they held a Linux Expo earlier this year too. Occasionally silly, a group of four that's sometimes hard to follow if they're all talking at once, but well worth your time.
- Keith and the Girl - another one with a (New York-based) couple talking about whatever they want, kind of interesting but not strong enough to stay on my subscriptions; I don't quite have the time for anything I'm not going to really look forward to the next episode of.