If you don't get enough email already, a new discussion group, MedStats, was created recently. MedStats is hosted on Google Groups. The main page for MedStats is groups.google.com/group/MedStats and details about the list appear at groups.google.com/group/MedStats/about. Previously, these discussion groups used some type of electronic mailing list software and were distributed by email. Or they were based on Usenet and people used newsreader software to monitor the discussion groups. More recently, Yahoo, Google, and others have developed web based systems that allow you to view the content of a discussion group on the web, or you could have the contents delivered to you by email. More details about google groups appears at groups-beta.google.com/googlegroups/tour/index.html. Information about Yahoo! Groups is at groups.yahoo.com/.
As part of the FAQ for STAT-L/sci.stat.consult, I listed other listserv/usenet groups related to statistics. http://www.childrensmercy.org/stats/faq/faq02.asp.
There is also a mailing list for Bioconductor. Details on how to subscribe are at https://stat.ethz.ch/mailman/listinfo/bioconductor
You can find an earlier version of this page on my original website.