The Sample: Newsletter and directory aimed to help subscribers discover other newsletters. Seeing as my own newsletter, RESTRICTED FREQUENCY, seems to trigger an equal number of unsubscribes as new subscriptions with each new edition sent out (at an almost consistent rate of about 0.43%), it's fair to assume that it has plateaued in its reach. Seeking new ways to get the word out and potentially grow one's audience is probably wise. THE SAMPLE is one of but a few ways I've come across.
“Galactic mind”—Rupert Sheldrake — Youtube