Google Groups: "rec.radio.amateur.moderated" is USENET technology which was (and still is to some) popular from the days of the internet over dial-up.
This group and Rec.Radio.Swap offer digest messaging which gives users the ability to get ONE email per day, rather than every message, plus one does not have to use USENET with their primary email address, thus eliminating SPAM.
What is your favorite online ham radio information source?