"Podcatchers, the programs that download and aggregate your
favorite podcasts, are popular on all platforms. Many are available
for Linux, including iPodder and Podget. But the truth is that you
don't need all that fancy stuff to harvest podcasts with Linux.
BashPodder is a quick CLI-based GPLed podcatching client. It's one
of the oldest ones out there, and may still be the best. It's
hands-on, no-frills -- and a perfect example of how a few
command-line statements can work together to do a powerful job.
"Written by Linc Fessenden of The Linux Link Tech Show podcast,
BashPodder parses the URLs of any podcast feeds you give it and
saves the podcast files to dated directories..."