Podfisher is the best way to get podcasts on the go.

Podfisher is a full-featured and easy to use podcast client that lets you track when new episodes are available and allows you to download or stream them instantly! With Podfisher, you no longer need to sync your iPhone or iPod Touch just to get the latest episode of your favorite shows.

FEATURES:
-stream episodes in-app for quick access over WiFi or 3G
-directly link to each podcast's iTunes page, letting you download episodes straight to your device and play them back through the iPod/Music app (episodes will even sync back to iTunes on your computer!)
-full access to each episode's show notes, including a built-in web browser to view links and additional content
-iPod library integration: see which episodes you have downloaded or synced to your iPhone or iPod
-control episode playback through Podfisher
-easily subscribe to your favorite podcasts by searching a huge database of shows