If you mean an anounce only list, yes I believe the is a way. If you mean as a lst serve where people can reply, yes there is a way. I own and run 3 lists on IO. You will have to export yoru list archives as MBox files but that should be doable from themailman interface.
Sarah Alawami, owner of TFFP.[excess quote and a solicitation removed by moderator]
We are investigating using Groups as a listserv to replace our current listserv currently on mailman. Is there a way to use it solely for that purpose?