Hi
Few suggestions:
1. The filter language (--expretrieve option), is again very flexible, but seemingly more designed for the positive filtering (select only matching messages), rather than negative one (download everything _except_ list of matches).
This makes it pretty difficult to create spam filtering rulebases.
2. According to the MAN page, you can use match rules for subject, author, from, #xrefs, #lines, #bytes and others. This is pretty nice, but you still cannot filter by individual message headers such as NNTP-Posting-Host (which can be very effective against spammers).
3. With all the filtering in place, it would be very nice to be able to run my own program or shell script from inside nget after each downloaded message. This may be used for more sophisticated spam filtering, custom logging or analysis. I imagine it should be very easy to do in code and can be great feature for the users.
Thanks!
Track