I've tried a bunch of iPodder aggregator programs. None have turned my crank. They've been quirky, unreliable, misbehaving beasts. All I want is a simple, faceless app that reliably sucks down the enclosures from a set of feeds.
Bashpodder is perfect! It's a BASH script, with a grand total of 44 lines of code (many of them are comments). You feed it a list of RSS feeds, and it sucks down the enclosures. It works fine via Crontab, so it can run invisibly in the background.
I'm running it now on the APOLLO XServe (I'll migrate it to my desktop box after the break), and it's slowly crunching through the backlog of podcasts I've missed. After it's caught up, I'll schedule it to run every morning at some ungodly hour so I get all the bandwidth I need, and the podcasts will be ready for me to drop onto the iPod first thing in the morning...
It would also be trivial to deploy Bashpodder as an auto feed mirror, complete with .m3u playlist files (but I'm not planning on doing that...)