Ixion is a list-server/mailing list sort of thing. If you send e-mail to the Ixion mail list it gets broadcast automatically to everyone else who is on the list.
Ixion was originally set up by Dave Edmondson in July 1990 at Queen Mary and Westfield College in East London. Malcolm "We Are Not Worthy" Jackson took over the running in 1993 and kept Ixion waffling for nearly ten years, until in January 2002 Ixion left Nottingham to live on a server owned by ixies. Originally called Ogri after the Ogri character in Bike magazine the name was changed to Ixion after a complaint by Paul Sample.
Once you're on the list you can send e-mail to email@example.com and it will be broadcast to everyone on the list. You'll receive mail from anyone else who e-mails the list too. There are about 400 people on the list, most of whom don't post ("lurkers"). The volume of traffic varies, but 300 messages per day is not unheard of. A digest version is also available i.e. you receive all your mail in one fix rather than in a steady trickle. Saves cluttering up your mailbox and avoids troubling your boss ;-).