Lists that are subscribed to other lists is certainly something that has been done before, and can be quite practical. For example, let's say you have a project with four lists: project-users (unmoderated, subscriber post), project-developers (unmoderated, subscriber post, private), project-bugs (moderated, public post), and project-info (moderated, public read-only). Let's say all of your high-level project announcements are posted to project-info. It makes sense to also send any post there to the project-users list, so that people there don't have to subscribe to both lists and so that the person who posts to project-info doesn't also have to send email to project-users. I believe mailman has this capability. I know that ecartis does, and it's easy to set up with smartlist (given that smartlist is really just a bunch of procmail recipes). The commercial listserv does this as well, IIRC. Would I suggest subscribing a bunch of lists to a single one? Sure, as long as the traffic generated doesn't get to be insane. You do need to remember that posts to this "explosion list" should remain local and not propogate to the parent lists. One thing that parallels this idea, and is probably more practical, is the RSS feed "planet" sites that aggregate News and blogs. I will say that the moment that tclug-list becomes an explosion list is the day I unsubscribe. ;-) Anyway, back to the grind. Chad