how to monetize email list?
there: i know at least the sourceforge.net email lists have ads on every mail going out.  hotmail did this and may still (does anyone still use hotmail?).  it seems like it would be difficult for a 3rd party to provide an ad network like the many web advertisers do because the ad generation would have to be integrated into your mailing list software and run on your server, which may put it out of the reach of many list operators.perhaps you should reach out to your own subscribers and see if any of them would be interested in advertising on the list.  setup a web form, run your own ad at the bottom of list emails saying "to advertise here go to ...".