The MUM consisted of various presentations and demonstrations and one which caught my eye was a presentation from Barry Higgins from Allness, who demonstrated using OSPF to distribute a black list of bad guys which were then null routed, a nice method of distributing 'firewall' rules on a bunch of routers automagically. You can view his presentation on Youtube.
I've recently been playing Vyatta vRouter appliances and wondered if I could apply a similar method of injecting a black list from an IDS (Intrusion Detection System) and having it distributed via BGP.