Due to an unusual set of circumstances, we had to turn off email for about an hour today. A combination of a new email virus/worm, disk space, and email lists, and mail scanning, all combined with some bad luck and we ended up allowing almost everyone on campus to recieve the latest Windows email virus/worm called W32.Beagle.B@mm http://securityresponse.symantec.com/avcenter/venc/data/w32.beagle.b@mm.html
We have made some changes to our setup so this same sort of circumstances should not happen again.