C-Span has begun podcasting on a trial basis, offering three weekly programs: The current events interview shows American Perspective and Q&A and the Book TV interview show After Words.
The copyright notice for the podcasts makes note of something that's often misunderstood about C-Span -- the programs are not in the public domain:
Except as specifically permitted by this policy, C-SPAN's RSS feeds and audio files may not be used for any political, commercial or otherwise unauthorized purpose. Any posting, retransmission, sale, public performance or other unauthorized duplication of the audio files is strictly prohibited.
C-Span is produced by a non-profit corporation set up by the cable industry that receives no government funding. All of its content is protected by copyright and the network explicitly forbids redistribution on the Internet.