Since I've been a Comcast subscriber, Comcast offered Usenet outsourced
to Giganews. This was discontinued effective September 16th, although
it won't be discontinued for existing users until October 25.
If you're a Comcast subscriber, please complain. I called customer
retention (the sales group you get when you call their customer service
number asking to disconnect service) and told them that Usenet was worth
$5 a month to me and they gave me a credit for each of the next 12
months. It's unlikely to change anything but it's more likely they'll
notice if a customer requests a credit.
For binary Usenet, http://giganews.com
/ or another premium service
For text Usenet only, http://individual.net
/ is the best there is.
There are alternatives. Don't use Google Groups. Don't lose access to
the most important newsgroup on Usenet.