Two of the most interesting phenomenons on the Internet right now are arguably blogs and podcasts. The former are personal diaries, and can be written by anyone from the fellow next door to executives in big companies. The latter can be considered something similar to "radio on demand". A podcast is simply a method for distributing multimedia files using the RSS standard. Clients exist for Windows, Mac OS X, and Linux. Depending on your needs, there are different clients you can use in Linux ranging from full graphical tools to simple shell scripts.
A fast and minimalist podcast client is BashPodder, a podcasting client written in bash that requires the bash shell, wget, and sed—all three of which are typically installed on any Linux system. This script will download the multimedia files from the sites named in the bp.conf configuration file and store them in a local directory for you to peruse at your heart's content with any audio player.
Another powerful podcasting client is jPodder, a java-based cross-platform client. jPodder not only provides a GUI interface to podcasting subscriptions, but it downloads selected items you're interested in and hands off the playing of the content to an appropriate program (based on mime-type associations) to listen to or to view. It can also be used to create your own podcasts by stepping you through production, the creation of the RSS feed, editing MP3 tags, FTP transfers, etc. jPodder is perhaps one of the most versatile podcasting clients available and can be freely downloaded at http://www.jpodder.com/
Once you've got your client, finding interesting podcasts is a breeze, using either http://www.ipodder.org
where you will find thousands of different podcasts that you can listen to.