The BBC make all of their podcast programme information available as an XML file.
Literally five minutes of XSLT gives me this:
$ xsltproc bbc-podcasts.xslt http://downloads.bbc.co.uk/podcasts/ppg.xml > bbc-podcasts.opml
outputs to: http://philwilson.org/code/bbc-podcasts.opml
which you can then render to something like this: http://tinyurl.com/2edfvs
Obvious improvements are grouping by radio station etc. but this will be very handy as-is for my N95 🙂