I've been using iPodder, a simple aggregator which takes care of checking for new podcasts, and downloads them for me. It also allows the option of running a custom command after each download.
Unfortunately there doesn't seem to be a possibility to create a playlist for each podcast, or an option to create a playlist containing a list of all current podcasts.
Perl to the rescue. A nice simple script, which can be run from iPodder after each download, and will generate m3u playlists which EphPod can then convert for my iPod.
my @casts = list_dir(".");
foreach my $dir (@casts)
next if (! -d $dir); ##check its a directory
my @files = list_dir($dir); ##list all the files
#create the playlist file
open(OUT, ">$dir.m3u") die "cant write playlist for $dir : $!";
foreach my $file(@files)
print OUT "$dir/$file\n";
#list the contents of a directory - exclude . and ..
my ($dir) = @_;
opendir(DIR, $dir) die "cant read dir $dir:$!";
while(my $file = readdir(DIR))
next if ($file =~ /^\.$/);
next if ($file =~ /^\.\.$/);